Last week, I was vacationing in Canada when an interesting commercial appeared on the TV. It was an ad for the sweetener, stevia, featuring enthusiastic consumers growing plants at home. Needless to say, it caught my attention. I had heard that stevia extract came from a ‘natural’ source. But I’d never stopped to consider what that meant from a gardening perspective.
I decided to dig deeper. Continue reading
‘There are always flowers for those who want to see them’ – Henri Matisse
For most of my life, I’ve been more attracted to ornamentals than to wildflowers. Even though I’ve noticed many beautiful species in the landscape, I’ve never really taken the time to observe them. You might say, I’ve been wildflower blind. Continue reading
Just the other day, I was working with a bunch of Master Gardeners preparing a garden for the county fair when one of them noticed a bare space. Sure enough, in one of the central beds, a group of plants had recently given up the ghost on a prominent corner. In no time, we all agreed that a lacy evergreen would be the perfect replacement. And that’s when I suggested chamaecyparis. Continue reading
Naturalistic plantings at the Denver Botanic Gardens
If you’re used to order in the garden, naturalistic plantings can seem a bit out of control. But installations such as New York City’s High Line are bringing this new, plant-driven approach more and more into the mainstream. That’s according to award-winning designer Carrie Preston of the Netherland’s Studio TOOP. She spoke recently in Maryland on how to incorporate naturalistic plantings into all types of landscapes. Continue reading
Monarch butterfly on swamp milkweed
Last week, I was manning the booth at the Master Gardener Demo Garden when someone plopped a tall, spindly plant down onto the table. It looked pitiful; the flowers were gone and the leaves had tiny holes in them. But upon closer inspection, I spotted a few lantern-shaped chrysalises and some colorful caterpillars working their way up the stems. The plant was none other than milkweed. And the ‘lanterns’ contained baby monarchs in the process of forming. Continue reading
Come August, a garden can start looking a little tired. Months of heat and bugs take a toll on summer blooms. That said, it’s also a time when many late–summer flowers are just coming into their own. All it takes is a little planning and you can extend the blooming season all the way until fall. Continue reading
Most flowering plants need lots of sun to keep on blooming. Still, over time, the blooms often start to diminish. That’s where deadheading can make all the difference. Not only does it keep plants looking neat, but it also promotes new growth and re-flowering. And, there’s nothing quite like getting a plant to re-bloom that otherwise looks done for the season.
Simply put, deadheading is the practice of removing spent (dead) flower heads from a plant.
Dried poppy seed heads
All plants follow the same life cycle; that is, they grow, produce flowers, set seeds and die. No sooner do the blooms fade, and a plant turns its energy to setting seed. That said, by removing spent blooms, you can delay production of seeds. This in turn redirects energy to flowering. The result is a healthier, more vigorous plant that blooms for a longer period of time.
Regular deadheading benefits all blooming plants. However, the world of flowers is diverse and many species require their own specific methods. Here are tips on how to deadhead six key types of flowering plants:
Purple garden phlox
These types of flowers include tall, leggy plants like phlox, yarrow, daisies. To keep your plant looking neat, remove the spent flowers just before they die back completely.
A good rule of thumb is to reach into the plant and prune the spent flowers back to the first or second set of leaves. This not only helps hide the cut, but it also encourages the plant to bush out as it produces new blooms. I vary the lengths at which I cut to keep the plant shapely.
Long-stemmed orange daylily
Flowers like daylilies and hostas have no leaves on their stems. Cut the entire stalk back to the base of the plant once it has finished flowering.
Multiple flower spikes of salvia make pruning tedious
Once the initial flush of flower spikes start to brown, salvias look like they’re done for the season. With proper deadheading, however, you can encourage them to keep on blooming.
What may at first glance look like a single flower stalk is actually three flower stalks growing together – a central stem surrounded by two, smaller ones on either side. As soon as the central stalk starts to wither, remove it. This will encourage the side shoots to grow. Then, once the side shoots lose their color, cut them off too.
Deadheading salvias in this way can encourage the plant to re-bloom at least twice and sometimes three times during the season, especially if you feed it mid way through the summer. Try one of these stunners for great summer color: Salvia patens Cambridge Blue, bright red Salvia Jezebel, or the traditional purple/blue favorite Salvia x sylvestris May Night.
Coreopsis verticillata
Bushy perennials like coreopsis can be encouraged to produce a second round of blooms way past their typical flowering time.
However, it can be tedious deadheading so many tiny flowers. Instead, I grab big chunks of spent blooms in one hand and shear them back with a pair of long-blade shears in the other. This not only encourages the plant to re-bloom a week or so later, it keeps thinks looking tidy. Try soft yellow Coreopsis Moonbeam for reliable blooms all summer.
With roses, the number to know is ‘5’
Most of us know that roses need to be deadheaded to flourish. Remove withered blooms by pruning back to above a five-leaflet leaf, cutting on an angle.
Geraniums need consistent deadheading to look their best
All annuals need to be deadheaded regularly to thrive (with the possible exception of begonias, in which case you should prune the leaves.) Popular annuals like geraniums and petunias must be constantly snipped, pinched or cut back to keep flowers looking neat and to encourage blooming. For a more in-depth tutorial on how to prune these annuals, click here for How To Keep Your Potted Plants In Shape All Summer.
Butterfly weed is a prolific self-seeder
Some flowers, like columbine, echinacea and butterfly weed are prolific self-seeders. If you’re looking to produce lots of new baby plants, leave the seed heads on and they’ll quickly spread around your garden.
It’s rare to damage a plant by cutting it. Use common sense while removing spent flowers, taking care to hide your cuts under existing foliage. Remember to sterilize your pruners regularly to prevent spreading disease between plants. You’ll reap the rewards of a new flush of blooms!
Looking for garden design ideas? I post photos of my landscape projects on Instagram.
Monarda, or bee balm, is a spectacular plant when grown under the right conditions. With plenty of sun and well-draining soil, it will flower from mid to late summer. That said, the plant has an annoying predisposition to powdery mildew that can make it an eyesore in the garden. So, recently researchers at Delaware’s Mt. Cuba Center set out to identify which varieties offer the best resistance. Continue reading
Every year, I make a list of things I want to achieve or change in my garden. But the year passes, I get busy planning my clients’ landscapes and before I know it, it’s mid summer. That is not an ideal time to start something new in the garden.
I’ve promised myself that this year, however, will be different. All those ideas I’ve jotted down in my garden notebook? I plan to convert at least some of them into reality. And January is the perfect time to sit down and create a plan for just how all of it will happen. Continue reading
Minus some advance planning, fall usually spells the end of the garden. But if planted in spring, dahlias will flower non-stop through autumn. Lately, I’ve been waking up to crisp mornings only to discover more and more blooms. Who knew October could bring so many fresh flowers?
For some, dahlias may not be all that big a deal. But for me, the first time I saw the majestic, 10-foot flowers left an indelible memory. It was the 1960s, and I was a kid growing up in Delaware. Smack dab in the middle of suburbia, on the corner of two heavily-traveled streets, there was a small working farm. In the summer it produced fruits and vegetables. But in September, it grew dahlias.
And these weren’t your everyday 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 gently swayed in the breeze, solemnly saluting as we drove by.
Craning my neck out the window, I’d watch until they disappeared, slowly dissolving into a sea of rainbow colors.
And thus began my love affair with these beautiful flowers.
Dahlias are classified as tender perennials, meaning they may be annual or perennial, depending on the climate. They typically start blooming in August with other late-summer flowers. But the best thing about them is that they don’t stop blooming until the first frost, or roughly right around Thanksgiving.
And in spite of their reputation for towering stems and gigantic blooms, the plants come in all shapes and sizes. Dahlia types can range in height from the very tall specimens of my childhood to just under one foot. Planting the tubers is easy. Just dig a hole 6 to 8 inches deep and drop them in with the ‘eyes’ facing up. Three or more tubers per hole usually gives the most colorful effect.
Still, it goes without saying that the most notable feature of all dahlias are the flowers. These can range in diameter from 2 inches to almost one foot. And among these, there are specific dahlia types, each with its own specifications. For example, there are species with single, double and semi-double petals. And there are unusual shapes like spherical or cactus. There are also types that resemble flowers such as anemones, peonies or orchids.
Waterlily dahlia ‘Pam Howden’
Notwithstanding the variety, one thing all dahlia types have in common is their dazzling color. These flowers come in a seemingly infinite array, including all shades of pink, red, scarlet, orange, purple and yellow. Moreover, the flower petals often come painted with strips or tips of another color. (There are also creamy ones as well as many brilliant white species.)
In sum, with so many options to choose from, how do you decide? One way is to familiarize yourself with the most common types. You may be surprised to find that some don’t look like the ‘typical’ dahlia.
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 tubular shaped florets and an outer ring of one or more rows of flat ray petals.
Anemone dahlia ‘Polka’
Orchid dahlias have open centers 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 shaped like balls and feature double flowers with rounded or blunt tipped florets. Pompons are slightly smaller than ball dahlias.
Orange ball dahlias – notice the slightly flattened shape
The perfectly round pompon dahlia ‘Franz Kafka’
Decorative dahlias are doubles 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 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 reach an average height of around 40 inches.
Orange cactus dahlia
Semi-cactus dahlia ‘Aloha’
There are 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? Every year, among the ten top things I want to achieve or change in my garden, I resolve to plant more. Here’s how.
Dahlias are sold as tubers and need to be planted after the ground has warmed up and there’s no danger of frost. I usually plant mine in the late spring just around the time my tulips have faded. Plant the tubers in well drained soil in full sun for best results. You can also pot them up indoors a couple weeks beforehand to give them a head start.
Dahlia tubers need to winter indoors in a cool, but not cold, space
Dahlias are considered tender in my neck of the woods (Zone 6), but hardy outdoors in zones 8 to 10. That means that once they’re done flowering in the fall (or right after the first frost), I must dig them up. I then label them and store them in a dry spot in the basement. Click here for the USDA Plant Hardiness Map to see where you fit.
To see photos of my garden designs, including plant lists, check out my Instagram at carole.herebydesign. I post seasonally from spring through fall.
