Top Holiday Plants And How To Keep Them Blooming

Soon, many of us will be receiving gifts of holiday plants with no clue what to do with them. Sure, the seasonal blooms look great in their decorative wrappings, but too often, just one week later they’re already showing signs of distress. Why toss these beauties in the trash when there’s still so much floral potential? Here’s how to keep your holiday plants looking their best and blooming well past the holiday season.


The best thing you can do for your holiday plant is to remove its decorative wrapper. All plants need good drainage to maintain good health. Foil wrappers and containers without drainage holes prevent water from escaping, meaning your holiday plant will sit in water every time you water it. You might have noticed the signs – yellowing leaves and sagging flowers? Since waterlogged soils leave little space for oxygen, the roots start to rot and very soon after, the plant dies.



I love receiving gifts of this beautiful succulent. The tiny clusters of orange, yellow, red or pink flowers remain attractive for weeks and the deep green, glossy foliage provides a dramatic backdrop. It’s crucial, though, to remove the container when watering. Succulents need good drainage and will rot if they receive too much water.

No forced blooms here — kalanchoes naturally bloom indoors during winter and early spring. Place your gift in bright light so it can receive at least 2 hours of sun, and water it every 2 weeks when the top of the soil feels dry. Keep it away from drafty doors and windows, which will spell the death of this holiday plant.



My house is often filled with cyclamens at holiday time. I love the plant’s upswept, fluttery petals and deep green variegated leaves. Florist cyclamens have been bred over more than 150 years, and today there are many new colors, petal shapes, sizes and fragrances to choose from.

Cyclamens can be pretty temperamental, though. Since they prefer cooler temperatures (below 70°F is ideal), their leaves will yellow and their flowers will droop if they get too hot. The plants are also very sensitive to watering — both too little and too much water will cause much the same effect. To keep your holiday plant in shape, remove it from its wrapper or container and water thoroughly only when the soil surface feels dry to the touch. Take care not to let any water touch the sensitive leaves or flower stems. After the plant has drained thoroughly, return it to its container.



These gorgeous tropical flowering plants are known for their bright red, heart-shaped ‘flowers’ which are actually spathes, or a kind of leaf that grows from the base of a spike of flowers. (Anthurium flowers are the yellow spike in the middle.) What makes this holiday plant special is that with proper care, it can remain in almost continuous flower for weeks, with some blooms lasting two months or more.

Anthuriums grow best in medium to bright light (avoid direct sunlight, however.) Keep the soil consistently moist and for best results, use tepid water when watering. A consistently warm temperature is key to keeping this holiday plant looking its best, so avoid placing it near drafty doors or windows.

Phalaenopsis Orchid

Phalaenopsis orchid

Of course there are thousands of varieties of orchids to choose from, but most orchid gifts come in the form of the easy-to-grow Phalaenopsis (also known as the Moth orchid), which can bloom for up to 3 months. The plant flourishes indoors under normal lighting conditions and prefers the same temperatures that humans do.

Place your orchid in indirect sunlight and water once a week, making sure the soil remains moist just under the soil surface. Be careful not to overwater or the flowers will wilt and fall off. Orchids need good air circulation around the roots to prevent root rot, so make sure your decorative container leaves plenty of room for the plant to breath. And always remove the plant from its container when watering, returning it only after it has drained completely.

Christmas Cactus

Pink-blooming Christmas cactus

This beautiful flowering plant loves holidays. There are Thanksgiving, Christmas and Easter varieties. Some bloom at Christmas and then again at Easter with proper care. Most times, people don’t know which kind they’re gifting, so your cactus may or may not rebloom after the initial holiday flush.

Christmas cacti thrive in bright, indirect light and cool temperatures, away from drafts and heat sources that can stunt growth and burn leaves. Christmas cactus varieties are tropical cacti and, unlike desert cacti, cannot tolerate dry soil. Keep the soil evenly moist for best results and water only when the top inch of the soil has dried out.


Purple and white gloxinias

This holiday plant with its large bell-shaped blooms and gigantic fuzzy leaves is a show-stopper. Unfortunately, many people toss these holiday plants the moment they’ve stopped blooming. With proper care, however, gloxinias can become great houseplants, while continuing to bloom all winter.

Like orchids and cyclamens, gloxinias will start to wilt if they don’t like their environment. Unlike cyclamens, however, gloxinias prefer warmer temperatures and they thrive in partial sunlight. Ensure your gift has evenly moist soil and is placed in an area with high humidity (supplement humidity with an humidifier or tray with pebbles and water.) It’s important to keep the water off of the foliage when watering to avoid brown spot.

Gloxinias require a period of rest in order to bloom again. Once the flowers fade, your gift stands a chance of reblooming if you reduce watering by half and resume regular watering only when new growth begins to appear.


Amaryllis just beginning to bloom

Who doesn’t love amaryllis with their gigantic trumpet-shaped flowers and ultra long stalks? Deep red is most common, but they also come in pink, salmon and white. Amaryllis naturally flower in winter, making them the perfect holiday plant. I’ve been gifted amaryllis in several forms’ as a bulb, pre-planted in a beautiful container and as a full-grown plant, nearly in bloom.

If you’ve received a gift of a bulb, place your amaryllis in a warm, sunny spot and water it thoroughly, making sure to drain the pot well after watering. After growth starts to appear, feed the bulb once a week with a bloom booster fertilizer. Once the flower buds start to develop, move the plant away from direct sunlight to prolong the life of the emerging blooms.

After the blooms have faded, remove the spent flowers so the plant doesn’t go to seed, but preserve the stalk. Wait until the stalk yellows before removing in order to furnish food for the bulb (and subsequent blooms.) Move the plant back to an area where it can receive plenty of bright sunlight. Click here for detailed information from the University of Minnesota on how to coach it to rebloom indoors the following winter.


Poinsettias in the nursery

Like anthuriums, poinsettias’ flowers are actually bracts. The flower is the tiny cluster of yellow orbs in the center. While many people choose to toss this holiday plant after the festivities, I like to hang on to mine for a little bit longer.

Poinsettias fare better with lots of good air circulation. Remember to remove the foil wrapper (to prevent drowning your plant when you water it) and place the plastic pot on a saucer so water drains properly. Like all other holiday plants, poinsettias prefer a regular watering schedule, allowing the soil to dry out between waterings. Give your poinsettia plenty of sunlight to keep its colors looking bright and avoid fertilizer, which will hasten the decline of the colored bracts.

For more information on some of the new exciting poinsettia hybrids that offer more than the traditional red or pink, click here for photos from the U.S. Botanic Garden’s holiday display.

Spring Bulbs: Still Time To Plant Some Of These 10 Great Varieties

Spring bulbs in a formal garden setting

Yesterday I directed the planting of two thousand spring bulbs. We placed them individually in patterns and our very capable team dug them one-by-one into the ground. When they were finished, we dressed the bulbs with a thick layer of mulch and all stepped back to admire our handiwork. The garden felt as if it were bursting with energy with so much spring promise nestled snuggly underground.

In Maryland, it’s almost too late to plant bulbs; but according to Patrick Gravel, a local plant expert, as long as you can get the shovel in the ground, there’s still time. Of course, by now most of the on-line bulb suppliers are pretty much sold-out. But, a quick run to the local nursery could still yield some interesting results.

Gravel came up from Richmond last week to speak to my garden club on how to garden with bulbs. Below is a detailed breakdown of the great bulb varieties he profiled. If you’re up for the task, many of them are still out there just waiting to be planted.


For me, the challenge of planting spring bulbs (like now) is the colder weather. Just when I’m turning my attention indoors, the bulbs need to go in the ground. This sometimes requires the ability to dig lots of holes outdoors when the temperature is hovering around 40°F (like yesterday.) Still, if you can visualize what the spring will look like, the reward is directly proportional to the amount of energy you’re willing to expend.

Carpet of blue muscari and other spring bulbs (Keukenhof, Holland)


Allium – Also known as ornamental onions, these drought-tolerant and easy-to-grow late spring/early summer bloomers come in a wide variety of colors, sizes, shapes and forms. Tall varieties include the giant purple-flowering GlobemasterGladiator, and Purple Sensation, the reddish-flowered, oval-shaped Drumstick, the light purple, spidery-flowered Shubertii (Persian Onion), and the rosy purple-flowered Millenium, which is the 2018 Perennial of the Year.

Giant purple allium

Anemone – small in stature with good primary coloring, anemones are great naturalizers. They bloom early to mid April, topping out at 4” at most. The low-growing, daisy-like Anemone blanda, or Grecian Windflower, makes an ideal companion for tulips and daffodils. “A nice early groundcover if you’re waiting for something else to emerge,” said Gravel.

Anemone blanda

Crocus – Gravel thinks of crocuses as ‘little surprises’. You need to plant them early, though, since they’re among the earliest spring bloomers. (Plant most varieties in mid October-mid November.) Look for Giant Dutch crocus, and the even earlier-blooming Snow crocus. Autumn Crocus, which is not a true crocus, but a colchicum, bears purple-pink or white flowers in September or October and must be planted in August.

Dutch crocus

Fritillaria – A member of the lily family, these spring-blooming bulbs have unusual, bell-shaped flowers. Crown Imperial grows to 3′ tall and has lily-like foliage (with a grassy head tuft), Snake’s Head grow to around 1′ tall and have checkered petals and the purple to black-flowered Black Persian grows to around 3′ tall.

Snake’s Head fritillaria

Hyacinth – Gravel advises wearing gloves when handling hyacinths, because the oil from the bulb is an irritant. Highly fragrant, they naturalize quickly and are easy to force inside (more on that below.) Problems are they tend to be floppy. Gravel recommends planting them deeper to give them more structure or planting them with low caging to keep the blooms upright. Click here for Holland Bulb Farms’ selection.


Hyacinthoides – Not the same as hyacinths, these woodland flowers have nodding, bell-shaped flowers in bluish-lavender flowers. Commonly known as Spanish and English bluebells.

Spanish bluebells

Muscari – Commonly known as Grape Hyacinth, these high-fragrant, tiny spring bloomers form rivers of brilliant blue to purple color under taller spring flowers like daffodils and tulips.

Muscari, commonly known as Grape Hyacinth

Narcissus – Named for the Greek hunter who fell in love with his own beauty, narcissus come in a wide variety of sizes, shapes and forms. Some of the most common are: the traditional, single-flowered Trumpet, the slightly smaller Large Cup, the flat-flowered Small Cup with distinctly colorful edges, the clustered/layered cupped Double, the diminutive Jonquil, Tazetta (also known as Paperwhites), and Poeticus with its small cup edged with red.

Double daffodils

Snowdrops – “A very simple bulb, you can’t go wrong with these February-March bloomers and they naturalize easily,” said Gravel. Choose from Galanthus elsewii, Galanthus nivalis, and the taller Giant snowdrops, Leucojum aestivum.

“There are many, many different varieties of snowdrops out there with tiny, tiny differences, said Gravel. “It’s a really nerdy plant.”


Tulips – According to, there are over 3,000 registered varieties of this popular spring bloomer. Some of the most common are Darwin, Triumph, Double, Fringed, Parrot, Fosteriana and Greigii. The diminutive species tulips like Bakeri are long-lived and great for the front of the border. Gravel recommends using chicken wire to protect the bulbs from digging animals.

Fringed tulips


This is much easier than you think. Gravel says the easiest bulbs to force are amaryllis and paperwhites. ‘All they really need is water,” he said. The rest of the spring-blooming bulbs require a 6- to 8-week cooling period that mimics their outdoor period of dormancy.

Plant the bulbs in well drained potting soil and keep in your refrigerator at a temperature ranging around 45 degrees F for 6 to 8 weeks. Keep the soil moist, but not soggy. After the cooling period, bring the bulbs out, place in a sunny location and enjoy.

Amaryllis bulb just beginning to sprout indoors

Patrick Gravel works at Sneed’s Nursery in Richmond, Virginia and lectures frequently on plants and plant life. He can be reached at

Five Reasons Your Trees Are Failing: A Bartlett Tree Expert Speaks Out

Trees are generally admired for their surface beauty, but their health and vigor springs from what’s underground. That’s according to Dr. Kelby Fite, Director of Research for Bartlett Tree Research Lab in Charlotte, North Carolina, who spoke to Maryland’s master gardeners last week. His lecture entitled ‘Managing the Landscape Below Ground’ provided a wealth of information about how to improve the life of the trees in our landscape. According to Fite, it all starts with the soil.

“We are all guilty of fouling up the soil,” he said. “But, it’s far easier to preserve soils than to remediate after they’re damaged.”

Before reaching for the fertilizer, Fite advises digging a little deeper into the source of the problem. Following are five common reasons that trees fail and what to do about them.

Soil Compaction

When it comes to tree health, nothing hurts a tree more than compacted soil. Often brought on by construction, soil compaction impacts trees at their roots, depriving them of essential water, oxygen and nutrients. It also makes it harder for a tree to anchor itself in the soil.

Compacted soil makes tree anchorage difficult 

Soil compaction occurs when soil particles are compressed by external factors like mechanical or human traffic, resulting in reduced pore volume (meaning there is less space for air and water.) Heavily compacted soils have a reduced rate of water infiltration and drainage and are often hydrophobic (meaning the water runs off). For a tree, this leads to poor growth, higher water needs and increased susceptibility to pests and disease.

Fertile, aerated soil

Compacted clay soil

Think of soil like a sponge, with large and small particles.

“What happens when we squeeze a sponge?” Fite asked. “We are increasing the amount of solid matter.”

It makes sense. Tree roots are extensive and with the exception of the taproot, located for the most part just 8 to 10 inches below the soil. They need space to grow. With compaction, however, many trees will never develop a taproot, instead establishing a network of weakened lateral roots that are unable to keep the tree vertical. And at the soil surface, the fine feeder roots (which under ideal conditions can extend 4 to 7 times the drip line of the tree) are compromised, too. This reduces a tree’s ability to absorb water, oxygen and nutrients and ultimately leads to its decline.

SOLUTION: Build away from a tree’s drip line and keep mowers and other machinery off the soil. For existing trees under stress, add a mulch circle. (More on that below.)

Raking up leaves deprives trees of important nutrients

This is a tough one. I’m not sure I’m ready to shred leaves and leave them all over my lawn. But think of it, we spend time and money to rake up one of our plants’ most important sources of nutrients, push them to the curb, then go to the store and buy them back again as mulch or soil additives.

“It’s not a great business model,” said Fite.

According to Fite, we are removing one pound of nitrogen per 1000 feet just by removing the leaves from our properties. This is a big loss for trees as well as other plants. And this doesn’t even take in to account the fossil fuels burned to operate leaf vacuums.

Our soils are low in organic matter because we are not allowing leaves to decompose like they do in the forest. When left alone, leaves return nitrogen and other organic matter to the soil. They also protect the soil surface, adding to its water holding capacity. And as they break down, they provide porosity and aeration, allowing more water to infiltrate the soil.

Shredded leaf mulch

SOLUTION: Shred your leaves with a mower and make leaf compost or leaf mold mulch (not the same thing.) For some great info on how to do both, click here for’s excellent article Rake leaves and make compost, mulch. 

Modified soils have higher pH which is bad for trees

In a perfect soil world, soils have a slightly acidic to neutral pH (a pH of 5.5 to 6.5). Urban and suburban soils, however, often contain debris left behind from construction. This generally results in a higher soil pH due to leeching from masonry walls and foundations.

Leeching from masonry leads to soils with higher pH

Trees growing in these locations may show signs of nutrient deficiency (like yellowing of leaves) and may be slower to establish. And irrigation water typically has higher pH, too. This means it gradually increases the pH of adjacent soils over time. This can result in a dramatic difference between the nutrient ability of your native soil and that affected by construction materials.

SOLUTION:  Do a soil test to determine the pH and get the turf out from under your trees. Lawn thrives on alkaline soil (that’s why we add lime.) But trees like a lower pH. All developed soils tend to have a higher pH and modified temperature, putting more heat stress on plants.

A soil test report from University of Delaware (my go-to destination for soil reports)

Lack of mulch

Mulch improves soil structure while providing protection to a tree’s roots. It supplies organic matter to the soil that reduces compaction. And it moderates soil temperatures, conserves moisture and eliminates competition from grass. Yet, many landscape trees are planted out in the lawn with no protection.

Fite recommends mulching out to the drip line of a tree if you can. It will help prevent ‘mower blight (or your mower banging into the trees) and also protect against stripping from string trimmers. Mowers, by the way, also contribute to soil compaction, especially when they’re operated in wet conditions.

Mowers contribute to soil compaction and can damage a tree

SOLUTION: Create a mulch circle around your trees. It will help protect them from mower damage and as the mulch decomposes, it will aerate the soil and provide nutrients.

Fertilizing when it won’t make any difference

According to Fite, fertilizer doesn’t fix everything. Pull a soil sample from around your tree first to determine whether or not to fertilize. Most soil labs will run diagnostics on your sample and send you back a prescription for what to add to your soil to improve its composition.

Before fertilizing, ask yourself what is the objective? If construction has occurred and interrupted a tree’s root zone, no amount of fertilizer is going to fix the problem.

And remember, although native soil usually contains lots of organic matter, during construction this layer is often buried under layers of sand or debris. Or sometimes, it’s stripped off entirely. No amount of fertilizer is going to bring life back to this kind of soil.

SOLUTION: Do a soil test to find out what your soil is made of before reaching for the fertilizer. Fix the soil first, then use fertilizer to adjust accordingly.


Fite offered a couple additional suggestions for how to get your trees back in shape (assuming you haven’t destroyed most of the root system by building too close):

Invigorate the roots

Many times the best thing you can do for your trees is to invigorate their roots. Bartlett uses an air spade, a tool that uses an air compressor to generate a high velocity jet of air to dislodge the soil. The rush of air breaks up and ‘tills’ the soil without removing it to a depth of about 8’ (the depth of the feeder roots). This method of improving the soil leaves root systems intact.

Air spade in use at Western Illinois University

The air spade was originally developed by the military to clear land mines. Nowadays, it is used by landscapers and arborists to invigorate roots. After the soil is excavated, add soil, compost and mulch to settle the soil back down. Then water the tree.

Look into Biochar

Mulch breaks down because the microbes eat it for carbon, resulting in it having to be replaced every year. Charcoal, on the other hand, is stable, meaning it lasts for centuries. Biochar is a fine-grained, highly porous charcoal that is added to soil to help it retain water and nutrients. It acts like a dry sponge, but on its own contains no nutrients, so blend with compost for best results.

Biochar acts as a dry sponge, but contains no nutrients

“Put the two together and magic happens,” said Fite.

Buyer beware, though, biochar is not regulated, so buy from a reputable source and read the label carefully.

Kelby Fite, Ph.D. is a VP and Director at Bartlett Tree Research Lab.

Tree ID: How To Be Your Own Best Detective

Giant tulip poplar in Orange, Virginia

I remember the first time I realized the value of knowing a tree’s name. I was walking with a friend along the C & O canal in Great Falls, Maryland when she began identifying the trees around us. As we passed, she stopped to observe different species, remarking on their personal characteristics and quality of growth. Suddenly for me, the woods took on an entirely new dimension.

Most of us feel more comfortable in public when we know people’s names and a little bit about them. I learned that day that the same goes for trees. Acknowledging each by name allowed us to communicate with and about them, opening a door into a world that had until that moment been only green.

Elm tree

Knowing a tree requires undivided attention

I’ve made great strides learning names of trees over the past decade. Still, I remain frustrated by the ones I don’t know. Just when I think I’ve nailed it, someone will present me with an oddball leaf I can’t readily identify. And, as a garden designer, most clients expect me to be not only an expert on shrubs and perennials, but trees as well.

So recently, I was happy to learn that the Audubon Naturalist Society (ANS) was offering a full-day lecture on native tree identification in Chevy Chase, Maryland. The lecture was held in a beautiful old brick home that serves as their location. Girded on all sides by dense woodland, the property features some of the most magnificent mature trees in Maryland.

Audubon Naturalist Society headquarters in Chevy Chase, Maryland

Our instructor, senior naturalist Stephanie Mason began our lecture with this quote from Edgar Allen Poe:

To observe attentively is to remember distinctively.

OK, Poe was speaking about investigating murders, not trees, but Mason feels the quote applies. To be a good tree identifier, you need to first become a good observer. She cautioned that even the experts don’t expect to identify everything correctly.

“It’s a big plant word out there,” Mason said. “If you know how to use a field guide, you’re already on your way. You have to go out and observe again and again. And then go out and observe again.”

And with that, we were off to the races.

Dried seedpods (samaras) of a maple

Five easy steps to identifying trees

There are many characteristics that can be used to identify trees, including overall size and shape of the tree, size, shape and arrangement of leaves, buds, bark , fruit and flowers. Most people use a combination of the above. Still, when attached to the tree, leaves are the most common identifying feature. We started by snapping off a twig with some leaves on it and asking ourselves these questions:

Step 1. Are the leaves single or compound?

A single leaf is attached to the twig on its own, while a compound leaf consists of a number of leaflets that together, comprise one leaf.

Step 2. How are the leaves arranged on the tree?

One important tool to identifying trees is to determine the placement of the leaves on the tree. Are the leaves growing opposite or alternate to each other on the twig?  To aid in the task, Mason shared with us a useful mnemonic. (This is used for remembering which trees have opposite leaves in our area.)

MAD HORSE    Or, Maples, Ashes, Dogwoods and Horse chestnut.

Step 3. What do the leaf margins look like?

Next is to zero in on the leaf itself. Are the margins smooth, wavy, toothed or lobed? (In some cases, you may need a magnifying glass to better observe the leaf margins.)

Step 4. What is the veining like on the leaf?

Turn over the leaf and look at the veining. There are two types of veining that can occur. Palmate leaves have veins that spread outwards from a central point, just like fingers on a hand. A maple leaf is palmately veined.

Pinnate leaves have veins that extend outward from a central spine, like a feather An oak leaf is pinnately veined.


Step 5. What do the terminal buds look like on the twigs?

This simple step often helps ID the tree the fastest. For instance, the terminal buds of flowering dogwood trees have a distinctive onion shape.

Terminal bud of Cornus florida, Flowering Dogwood/Stephen J. Baskauf

The Dichotomous Key

Dichotomous keys are useful tools that help people identify things in the natural world. The keys consist of a series of choices, A or B, that lead the user to the correct name of the species. Our tool for the day was ‘Common Native Trees of Virginia’, but there are many other dichotomous keys for identifying items from all over the world. Tree ID experts use them all the time.

The keys always start with the same choice, Choice Number One. Once you have determined which answer best describes your specimen, you go to the number where the choice directs you. You follow the numbers in this way, continuing to read and select answers until you arrive at the name of the tree. It’s a lot like a treasure hunt and an invaluable resource for deciphering plant life in your area.

Interested in learning more? There are dichotomous keys for just about everything. Look for one that applies to trees in your area and get started! (Click the link above for a list of what’s available on Amazon.) I guarantee it will open up a whole new world.



Dreamy Dahlias: 10 Ways To Identify Your Perfect Type

A cactus dahlia blooming in my garden

Fall may be poking a tentative finger into my garden, but my dahlias still think it’s summer. Every morning I wake up to a multitude of new blooms. And, no matter how many I harvest, the next day there are still more waiting to be cut. To me, October means breakfast with an armload of fresh flowers, their brilliant, flat-tipped petals still wet with the morning dew.

My first memories of dahlias date back to the 1960s when I was a kid growing up in northern Delaware. This was a time when suburbs were still interspersed with working farms in an eclectic mix of cow pastures and neatly manicured lawns. One such farm was located at the crossroads of two suburban streets, Silverside and Faulk. In September, the portion of the property adjoining the busy corner was transformed from grassland into a field of dahlias.

And these weren’t your ordinary dahlias, mind you, many were the gigantic, dinner plate size; the kind that drives a kid mad with desire to jump out of the car just to be among them. Standing as tall as adults, they would gently sway in the breeze, tilting their giant heads in salute as we slowly motored by.

I’d crane my neck out the window and watch them until they gradually disappeared, dissolving as one into a sea of rippling colors.

Thus began my love affair with dahlias.


So many dahlias, so little time

Dahlias are tuberous, herbaceous perennials that are native to the tropics. They are members of the Asteraceae family. Classified as tender perennials, they may be annual or perennial, depending on what the climate is like where you live.

The flamboyant flowers are perhaps best known for their tall, celery-like stems and gigantic flowers, but they come in all kinds of sizes. These range from the very tall (around 7 feet) to just under 12 inches. There are thousands of varieties.

Dahlia flowers also range widely in size, from a diameter of around one foot to just under 2 inches. And within the different size groups, there are different flower types, each with their own classifications. These include dahlias featuring single, double and semi-double petals, those that have unusual shapes like spherical or cactus, and varieties that resemble other flowers like anemones, peonies, orchids and waterlilies.

Waterlily dahlia ‘Pam Howden’

Last but not least are the dazzling colors – a seemingly infinite variety of gorgeous pinks, reds, scarlets, oranges, purples and yellows, as well as creamy and brilliant whites. Many flower petals often come with strips or tips of another color.

So, with so many options to choose from, how to decide? One way is to get acquainted with the most commonly used classifications. These help define each dahlia’s unique shape and structure and can aid in their selection.


Single-flowered dahlias feature a single row of flat or slightly cupped ray petals surrounding a central disc.

Single-flowered dahlia

Semi-double dahlias have two or more rows of petals surrounding a central disc.

Semi-double dahlias

Mignon dahlias are similar to single dahlias except their petal florets are rounded and their disc flowers have no more than two rows.

Mignon dahlia with burgundy/black foliage

Anemone dahlias have an inner disc made up of elongated, tubular shaped florets and an outer ring of one or more rows of flat ray petals.

Anemone dahlia ‘Polka’

Orchid dahlias are open centered flowers with just one row of ray florets surrounding a disc. The petals are often overlapping and curled for most of their length.

Orchid dahlia

Collarette dahlias have one row of flat petals surrounding a disc as well as an inner wreath of shorter petals called the ‘collar’.

Collarette dahlia ‘Mary Eveline’ plum red petals with white ‘collar’

Ball and Pompon dahlias are ball-shaped and feature double flowers with rounded or blunt tipped florets. Ball dahlias have round, cupped petals that are spirally arranged in a honeycomb shape. The flower may be slightly flattened. Pompon dahlias are slightly smaller. They are known for their perfectly round flower head.

Orange ball dahlias – notice the slightly flattened shape

The perfectly round pompon dahlia ‘Franz Kafka’

Decorative dahlias are double dahlias that feature flat, oval petals with tips on the end. Formal varieties have regular, evenly placed petals, while informal varieties tend to be arranged in a more haphazard way. Both varieties grow to over 40 inches.

Decorative dahlia ‘Lisa Dark Pink’

Cactus and semi-cactus dahlias. Both have narrow pointed petals that roll back on themselves, giving them a spiky look. Cactus types are rolled for their full length, while semi cactus types include a mix of flat and rolled petals. Both are considered double flowers and reach an average height of around 40 inches.

Orange cactus dahlia

Semi-cactus dahlia ‘Aloha’

There are so many other varieties, including peony, waterlily and stellar, not to mention the celebrated ‘Dinner Plate’ which falls under numerous categories. The Miscellaneous Dahlias category alone includes hundreds of varieties.

Ready to add dahlias to your garden? (or in my case add more). Here’s how.

When to plant

Dahlias are sold as tubers. I like to plant them just around the time my tulips have faded, in well drained soil in full sun. You can also pot them up a couple weeks beforehand to give them an early start.

Considered hardy outdoors in USDA zones 8 to 10, dahlias are considered tender in my neck of the woods (Zone 6.) Once they’re done flowering in the fall (or right after the first frost), I dig them up, label them and store them in a dry spot in the basement.

Want to learn more about dahlias? Visit Longwood Gardens’ annual dahlia show, held each year in Kennett Square, Pennsylvania. Looking for a great place to buy tubers? Check out the beauties at Eden Brothers, one of my favorite online sources.

Dahlias were named for the 18th century Swedish botanist Anders Dahl.


The September Garden: How To Wind Down On A High Note

My September garden

The end of September can be a tough time for gardens. Leaves lose their deep green luster, stems start to brown and many perennials have simply lost their will to survive. Add to that the fact that the lower the sun gets in the sky, the more dull colors can appear and suddenly, the same flowers that looked so vibrant in summer begin to take on a more muted, less enthusiastic look.

Still, a September garden can hold plenty of attractions with many great plants to choose from. It just takes a little spring planning with an eye towards fall, and you can have a beautiful garden that will provide color and blooms all the way until frost.


When planning your September garden, take a cue from the fall landscape and choose blooms in brilliant shades of red, orange and yellow. Even though they’re bright, these colors will look softer under a lower sun. Think dusty reds, golden yellows, tangy oranges and throw in some deep purples to add drama.

One of my garden combos, sedum, coreopsis and cranesbill geranium

And don’t forget pinks. They make a nice transition between all of the other hot colors.

Pink Japanese anenomes

Dried pink blooms of PeeGee hydrangea


There’s no right or wrong when it comes to removing dried seedheads. I leave the elegant forms of thistle, coneflower and rudbeckia to ride out the winter. Seedheads give architecture to the September garden where they pose as sculptures amongst all the fall blooms.

In September, the dried blooms of my coreopsis add color and dimension to my garden


Often at this time of year, things are looking pretty straggly. Aside from pruning things back into bounds, a new layer of mulch can do wonders for a garden. Dark brown mulch acts as a clean backdrop, helping fall tones to ‘pop.’ Plus, the aroma of new mulch always speaks ‘new.’

I’m currently a big fan of mulch made from shredded leaves. I buy it locally from University of Maryland. Not only does it keep neat and hold its color, but it continually feeds and conditions the soil, making for better, longer lasting blooms.


Here are some of the flowers that are still going strong in my September garden. Some of them have only just started to bloom.

Purple lisianthus

Sedum ‘Autumn Joy’ (I cut mine down by half in June so it blooms in September)

Dahlias are the stars of the September garden

Dahlia ‘Aloha’

Roses love the return of cooler weather

Rosa ‘Cardinal Richelieu’

Butterfly Weed

Sweet Autumn Clematis

September planters filled with sweet alyssum and lantana

This re-blooming white iris just reappeared in my garden. The bright white seems a little shocking amongst the other warm colors, so next year I’m switching it out for purple.

White seems a little jarring this time of year

Cranesbill geranium

Smoke bush, Cotinus coggygria ‘Royal Purple’

For other great fall planting ideas, click here for last year’s blog post on Maryland’s beautiful Brookside Gardens.

How does your garden grow? Join the discussion and share your ideas for great blooms for September!



Ten Great Ideas For Decorating With Gourds

If you’re like me, every October, when those big boxes of ornamental gourds land at the grocery store, your mind whirls with possibilities. The cute little shapes seem to embody the essence of fall. The problem is that once you get them home, the gourds are a bit lacking somehow. Sure, they look OK on their own in a bowl, but if you really want to get creative, design-wise, you’ll need to add some key seasonal ingredients.

Where did gourds come from, anyway?

Hard-shelled gourds have been around for a very long time. Archeological specimens indicate the bottle gourd (pictured below) was being grown as a domesticated plant in the Americas as far back as 10,000 years ago. It’s still a mystery as to how the gourds got to the New World from their native Africa. But a recent study indicates they may have floated here on ocean currents.

Bottle gourds growing in a garden

Today in the United States, there are three types of gourds that are typically grown: Lagenarias, or hard shells, that are mainly used in crafts; Luffas (also spelled loofah), most commonly used as sponges and Cucurbitas, the ones we call decorative or ornamental.

Cantine variety of ornamental gourds

Ornamental gourds are a whole lot smaller than ordinary gourds. Although some people eat them, they are more commonly known for their curious forms. These include such catchy names as bottle, kettle, pear, crown of thorns, egg and the popular cantine (those little pumpkin-shaped ones.) The unusual shapes are due to the little gourds’ tendency to cross-pollinate with each other as well as with pumpkins and squash. This allows for an endless supply of design possibilities.


Designing with ornamental gourds: Key elements

A good plan of action before getting started on your design is to first assemble some seasonal items that will add color and interest to your arrangement. If you’re considering a dry arrangement, leaves, twigs, nuts and feathers act as great accents to gourds. Try pheasant feathers, curly willow branches, walnuts or pinecones.

Pheasant feathers

Curly willow branches at

Pinecones add texture

Walnuts’ large size make them the perfect accompaniment to gourds

Or, you can carve out your gourds to make room for flowers, berries or vines. Try hypericum berries, orange bittersweet, purple, red or orange dahlias or yellow lilies.

Hypericum berries

Orange bittersweet

Assorted dahlias

Yellow lilies provide good color contrast

You can even add votive candles.


Putting it all together

Ready to get started? Here are some great sources of inspiration incorporating many of the items listed above. Click on the links for more detailed information about each idea.

1. Mini “pumpkin” and gourd wreath, Southern Living

Helen Norman for Southern Living

2. White gourds in dough bowl with cabbage and pine cones

3. Green gourd vase with red flower

4. Hollowed out gourds with votive candles

5. Purple and orange dahlias with bittersweet berries and leaves in acorn-shaped gourd vases

6. Orange and yellow gourds in a brown rustic basket

7. Minimalist sculpture with orange zinnias, flax leaf and feathery grass

8. Simply elegant: orange gourds in tall, thin vases with single branches of wild ivy

9. White gourd vase with pink gerbera daisies, magnolia leaves, mini green cantine gourds, ornamental cabbage and evergreen sprig

10. Stacked gourds in iron trellis with potted yellow mums

Happy designing!



Take The Quiz: How Well Do You Know Your Asters?

Aster Frikartii Monch

One of the many things I love about late summer are the throngs of colorful, star-shaped blooms that populate the landscape. The flowers congregate along roadsides, drift lazily across meadows and form neat combinations by houses and in town squares. Most of us are well acquainted with the yellow ones (sunflowers), but less aware that the brood also comes in shades of red, pink, purple and white. The flowers are all part of the Aster family (Asteraceae), the largest and most diverse group in the plant kingdom.

The scoop on the Aster Family

You may have noticed some of the flowers’ shared characteristics; many feature a round central disk surrounded by colorful petal rays. The Aster family is exceedingly large and numbers in the tens of thousands. According to The Plant List, there are currently 1,765 genera of flowering plants and over 27,000 known species growing in diverse climates all over the world.

Gaillardia or Indian Blanket Flower

The botanical name Asteraceae comes from the Greek ἀστήρ meaning star, a reference to the star-like shape of the flowers. But some call the family by its common name, Daisy, from the Old English meaning ‘day’s eye’ (a reference to the flowers’ petals that open at dawn.) Still others refer to the Aster family as the Compositae family, since the inflorescence is a composite of many tiny, individual flowers.

What’s special about Asteraceae is that while at first glance they make look like one flower, they are actually composed of many, all inserted on a common flower head. Of these, there are two types of flowers that may occur. Tubular, petal-less florets are found in the center of the flower disk while flat, ray-shaped florets (resembling petals) are found at the perimeter.

Zoom in on the photo and you’ll see the flowerhead is not flat, but actually made up of hundreds of tiny flowers.

Leucanthemum (daisy) displaying both tubular and ray florets

Within the family there are also several variations. Some flowers have only disk florets, others only ray, and then there are members like daisies, coneflowers, common sunflowers and asters that have both disk and rays.

Flower head of Echinops ritro, Globe Thistle, contains no petal florets

Scientists believe the highly specialized flower head, which also contains seeds and nutrients, helps the plants to store energy during periods of drought and possibly also contributes to their longevity. I know in my own experience that once established, my Aster family members like coneflower, daisy and blanket flower do indeed require little water. And certainly the roadside gardens filled with native sunflowers, daisies and asters are living proof of these flowers’ remarkable survival ability.

Of course every family has its outliers, and the Aster family has a few. These include the food crops lettuce, chicory and globe artichokes. Notice the two types of florets on the mountain lettuce below.

Mountain lettuce, Latuca perennis

Perhaps the most difficult members of the Aster Family to tell apart are the yellow ones. Superficially, many of the flowers look alike. But on closer inspection, their disk and ray flowers are all slightly different.

Take the quiz!

Below are some well-known members of the Aster family found blooming in the late summer and fall. Can you identify them? (For answers and a detailed list of these common family members, please see below.)

Answers: (from top) Coreopsis grandiflora, Golden Marguerite, Rudbeckia (Black-Eyed Susan), Helianthus tuberosis (Jerusalem artichoke), Helenium autumnale (Common Sneezeweed), Helianthus annum (Sunflower), Heliopsis helianthoides (Smooth Oxeye), Gaillardia (Indian Blanket Flower), Arnica montana

If you’d like to add some of these beautiful flowers to your garden, or just be able to identify some more members of the family, following is a list of well-known species in the Aster family and their value in the garden.



Echinacea (Coneflower)

Rudbeckia (Black-Eyed Susan)





Tickseed (Coreopsis)


Gaillardia (Blanket Flower)

Erigeron (Fleabane)



Oxeye daisy


Herbal Teas, Medicines and food

Calendula (Pot marigold)

Chamomile Anthemis)







Great Nectar producers

Helianthus annus (Sunflower)

Solidago Goldenrod


Insecticidal properties



Pulicaria (False Fleabane)








For a detailed list of Asteraceae, its genuses and where it fits in the plant kingdom, click here for USDA Natural Resources Conversation Service




Help Save The Monarchs With These 4 Great Milkweeds

Monarch butterfly on swamp milkweed

Last week, I was manning the booth at the Montgomery County Fairgrounds Demonstration Garden (yes, it’s a mouthful), when someone plopped a tall, spindly plant down onto the table. The plant looked pretty pitiful; the flowers were long gone and the paddle-shaped leaves had circular holes in them. But upon closer examination of the stems, I spotted a string of tiny, lantern-shaped pupae along with a company of black, yellow and white striped caterpillars. The plant was none other than milkweed and the chrysalises contained baby monarchs in the process of forming.

We placed the milkweed next to a grouping of Joe-Pye weed and sat back to see what would happen.

Things aren’t looking up for the monarch butterfly

Monarch butterflies are considered by many to be the ‘king’ of butterflies, with a wing-span of over 4 inches (hence the name, monarch.) But, according to the National Wildlife Federation, their population in North America is in steep decline. Over the past twenty years, monarch numbers have plummeted by an astonishing 90 percent, leading scientists to question what’s happening. They suspect the answer is tied up with milkweed.

Close-up of swamp milkweed, Asclepias incarnata

Why milkweed you might ask? Because milkweed is the host plant for monarchs, and monarch caterpillars will only eat plants in the family. But milkweed has been disappearing, too. Over the last couple decades, large-scale clearing of meadows and prairies for development coupled with heavy pesticide use has resulted in the plants becoming increasingly scarce, placing in jeopardy the tiny population that depends on it for survival.

The problem is so big that according to one National Public Radio (npr) report, monarch populations overwintering in Mexico that averaged around nine hectares from 1995 to 2002, in 2014 took up less than one.*

A migratory insect

Every spring, thousands of Eastern monarchs begin their annual migration across the Great Plains on their journey from Mexico to Canada, covering over 3,000 miles in the process. And every fall, they do the trip in reverse. The insects breed along the way, stopping three times to go through four stages of development: egg, larvae (caterpillar), chrysalis and adult butterfly. The new butterflies live for just four to eight weeks, long enough to fly further north and lay their eggs. Then the next butterfly continues the journey.

Millions of monarch butterflies flying in Mexico

This means that it takes three butterflies to make it all the way to Canada.

Incredibly, the fourth generation butterfly born in Canada lives a bit longer. This is the monarch that migrates back to warmer climates like Mexico. This butterfly lives for six to eight months, long enough for it to start the whole process over again in the spring. (To read more about the monarch butterfly cycle, click here.

A misunderstood plant

The milkweed family, Asclepias, is composed of more than 100 varieties of leafy plants. Tall and upright with long, elliptical-shaped leaves, milkweeds bear dense clusters of vanilla-scented rosy-pink or orange flowers. The plant owes its common name to the milky latex that oozes when a stem is snapped.

Milkweed provides all the nourishment the four generations of monarchs need to transform from larvae into butterflies. The baby caterpillars feed on the leaves until fully grown, and then attach themselves to a stem or leaf to start the process of metamorphosis. Once they hatch, the monarchs move on to other flowers to live out their short life.

Monarch chrysalis hanging from a milkweed stem

In addition to nourishment, milkweed provides other advantages to monarchs. As the caterpillars undergo transformation in chrysalis, they ingest toxic chemicals secreted in the plants’ sticky sap. These chemicals, called cardenolides, provide the caterpillars with a key defense against would-be predators such as birds and mice.

Monarch caterpillar munching on milkweed

Specifically, cardenolides are so toxic and bitter tasting to other vertebrate species that they have learned to associate bad taste with the butterflies’ distinctive orange and black markings. Although as adults, monarchs no longer eat milkweed, they are able to sequester the toxins that they ingested as larvae, providing them with protection against many predators during the remainder of their lifespan.

Monarchs’ distinctive colors help ward of predators

Monarch butterflies only lay one egg per leaf, but they lay eggs on lots of leaves and always on more than one plant. They are mini eating machines. Three days after it arrived to the fair, the caterpillars had devoured the plant they rode in on; in their place hung rows of tiny pupae.

Many of us are familiar with the roadside milkweed, but lesser known is that there are now many beautiful perennial varieties that can enhance your garden while helping you do your part to save the monarch species.

Common milkweed, Asclepias syriaca

Ready to save the monarchs? Here are some great new milkweed varieties to try, available at many local nurseries.

Butterfly Weed, Asclepias tuberosa

This bright orange beauty blooms from May to September. It just won Perennial of the Year for its brilliant flowers, hardy, upright stems and good drought-tolerance.

Butterfly weed, Asclepias tuberosa

Or, for a great yellow variety, try ‘Hello Yellow’, available through White Flower Farm.

Asclepias tuberosa ‘Hello Yellow’


Swamp Milkweed, Asclepias incarnata

Swamp milkweed ‘Cinderella’ available at

Or try a mix of hot colors, Asclepias Gay Butterflies Mixture, available at White Flower Farm.

Asclepias Gay Butterflies Mixture

Milkweed generally blooms from June to August. All varieties need full sun and well-drained soil. If you observe caterpillars or chrysalises on your plant, wait until the butterflies have flown away, then simply cut the plant to the ground.

* Monarch populations are measured in hectares, which roughly equal 2 1/2 acres.


Searching For Life At Yellowstone’s Grand Prismatic Spring

Yellowstone’s Grand Prismatic Spring

You cross a bridge over a burbling stream, clamber up a copper-toned hill and suddenly there it is: Yellowstone’s Grand Prismatic Spring. Standing on a wooden walkway, I inhale the warm, earth-scented vapors that glide across the turquoise water. Otherworldly? Yes. But, surprisingly even here, in this stunning but inhospitable place, there is life and things are growing.


First described in 1871 by the Hayden Expedition, the Grand Prismatic Spring is the third largest hot spring in the United States. Veiled in steam, it bubbles like a bathtub, offering a glimpse now and then into the churning caldron. The deep blue pool is impressive, but more surprising still are the tentacles of golden yellow, burnt orange and metallic green that fan outwards from the roiling waters, carving kaleidoscopic paths across the scorched soil.

Grand Prismatic Spring from new overlook trail

Upon seeing the spring for the first time, Ferdinand Hayden (the leader of the Expedition) wrote:

Nothing ever conceived by human art could equal the peculiar vividness and delicacy of color of these remarkable prismatic springs.

It’s enough to make your head spin.


Yellowstone’s hot springs

There are different kinds of hot springs at Yellowstone National Park. Grand Prismatic Spring is one. Old Faithful is another. Both result from groundwater that has been heated by molten magma and risen to the surface. In the case of Old Faithful, however, the hot water encounters blockages on its way up. This produces the famous geyser’s explosive eruption of steam.

Old Faithful

By contrast, the Grand Prismatic Spring is produced by hot water that rises to the surface through cracks in the earth’s crust. This allows for a continual flow of water that rises, cools and falls to the earth only to rise again.

Looking into the turquoise depths of the spring

Grand Prismatic Spring

Pouring almost 500 gallons of scalding water per minute into nearby Firehole River, Grand Prismatic Spring is the largest and most brilliant colored of Yellowstone’s many hot springs. The high temperature of the spring (estimated at around 160 degrees F) is responsible for the steam that hovers 24/7 above the crater.

Due to this cycle of heating, cooling and re-heating, the spring has developed rings of varying temperatures. The hottest water, which is located in the center, is too extreme for living things. However, as the water spreads outwards, it gradually cools, allowing for conditions more amenable to life to develop.

Bands of color at Grand Prismatic Spring

Happily, the viewing boardwalk provides safe passage for we humans atop the smoldering landscape. Embroidered with signs warning against the dangers of erring from the prescribed path, it features stories of how people have been scalded, children killed and family pets sucked into the vortex. Even standing too close to the spring can cause intense burns.

The viewing boardwalk at Grand Prismatic Spring

So how can life exist in such harsh conditions? The answer lies in the prismatic colors. Each of these stunning hues harbors billions of colorful microorganisms that live in the spring’s runoff channels. These ‘extremophiles’ (so named for their ability to live in conditions that were once thought too hot to host life) are not only surviving, but thriving, happily assembled in thick, microbial mats.

Forests in miniature

Microbial mats may not sound all that interesting until you consider that each of these burgeoning communities is in fact a miniature ecosystem functioning much like a forest. There’s a ‘canopy’ of microbes performing photosynthesis. And, there’s an ‘understory’ of organisms playing the crucial role of decomposition and recycling of nutrients back to the canopy.

The rainbow of colors that the mats produce depends on the temperature of the water. In the summer, the mats tend to be brown, orange or red and in the winter they tend to be dark green.

Microbial mats radiating outwards from Grand Prismatic Spring

Cynobacteria, marine bacteria that obtain their energy through photosynthesis, are one common organism found growing by the Grand Prismatic Spring. In the world’s oceans, cynobacteria occupy an important position at the bottom of the food web. At Yellowstone, however, they have had to make some ecological adjustments. These are evidenced in the distinctive yellow/orange color of the spring’s outer ring.

Specifically, a certain strain of cynobacteria called synechococcus has learned to survive the heat by adjusting its ratio of chlorophyll to carotenoids. Yellowstone’s extreme temperatures, high altitude sun and lack of shade can quickly overwhelm the photosynthetic process. So synechococcus manipulate their photosynthetic pigments to reflect only certain wavelengths of visible lights. They do this by employing carotenoids as shields, which results in their summertime yellow/orange color.

Close-up of some of the microbial communities

And so it goes. As you move further from the spring, more and more lifeforms can be found. Synechococcus is now joined by chloroflexi bacger, whose combined colors read as orange. Finally, as the temperature cools, the communities of bacteria at the furthest points produce the darkest color, a molten shade of coppery-brown.

View of spring from bridge

Hard to believe these mini orange and brown ‘forests’ are existing right under our very noses. Life is pretty amazing.