Tag Archives: summer flowers

Pruning Hydrangeas: A Step-By-Step Guide For Old And New Wood

Posted on by carole funger

To prune or not to prune? This is one of the quintessential gardening questions. Recently, I asked a top landscaper in Virginia to weigh in on the issue. “When is the best time to prune hydrangeas without cutting off next year’s flowers?” I asked. 

“Never,” she replied with a laugh. “But your best shot is after they’ve bloomed.”

It turns out that knowing how and when to prune hydrangeas involves first, identifying what kind of shrubs you own. And it all starts with determining whether they flower on old or new wood.

PRUNING HYDRANGEAS THAT BLOOM ON OLD WOOD

Nikko Blue hydrangeas bloom on old wood

Old wood is quite simply, last year’s wood. Hydrangeas that bloom on old wood set their flower buds in late summer on stalks that have been on the plant since the previous year. 

Hydrangeas that bloom on old wood include the mophead, bigleaf (macrophylla), lacecap and oakleaf varieties.  

Oakleaf hydrangea is recognizable by its foliage that resembles oak leaves

In terms of pruning, these beautiful shrubs require very little. But if you must, knowing when and what to cut is key. That’s because the more old wood you take, the fewer flowers you’ll have next summer. 

Follow these three steps to maintain the health and vigor of your old wood hydrangeas:

  1. Immediately after flowering (and no later than July), prune flowering stems back to a pair of healthy buds.
  2. In late winter or early spring, prune out weak or damaged stems. Remove no more than 1/3 of the oldest stalks, taking them down to ground level.
  3. Repeat the process every summer to rejuvenate your shrubs and control their shape.

PRUNING HYDRANGEAS THAT BLOOM ON NEW WOOD

Limelight hydrangeas bloom on new wood

Hydrangeas that bloom on new wood set their flowering buds on the current season’s growth. Since their flowers come from new growth from the base of the plant, they can be pruned almost any time of year, except summer.

Hydrangeas that bloom on new wood include the smooth, panicle and limelight varieties. 

Follow these three steps to maintain the health and vigor of your new wood hydrangeas:

  1. Cut off faded blooms in late summer to improve the looks of the shrub.
  2. Prune out the oldest canes to improve vigor.
  3. Cut back the entire shrub in late winter before new growth starts to appear.

Additional tricks of the trade include leaving some of the older branches as a framework for new growth (these types of hydrangeas tend to open up and get floppy.) Many gardeners also advocate cutting the shrubs all the way back to the ground, which often produces bigger flowers.  

‘ANNABELLE’ 

Considered the crème de la crème of all the varieties that bloom on new wood, Hydrangea arborescens Annabelle is what is called a ‘smooth’ hydrangea. Smooth hydrangeas are known for their giant white blooms. They are native to the southeastern United States.

Distinctive white blooms of Hydrangea ‘Annabelle’

What makes Annabelle so special is that it not only produces enormous, pure white flowers from June to August, but it also stays compact, growing to just 3 to 5 feet tall and wide. At first glance, it can be hard to tell this cultivar apart from other white-blooming hydrangeas. However, a number of gardeners go by this golden rule:

Annabelle flowers open lime green in early summer, change to bright white mid-summer and then switch back to light green in late summer before turning tan in the fall.

More recently, an improved version of Annabelle called Incrediball has been developed. It features basketball-sized blooms and thicker, stronger stems that won’t flop over. In fact, they’re so sturdy that they’ll stay upright even in a rainstorm. 

‘Incrediball’ features 12″ flower clusters and blooms on new wood

Most professionals recommend pruning hydrangeas like Annabelle to help control for shape and to increase blooms. For this reason, many gardeners cut them back to the ground (within 6″) in late winter or early spring. Some say this encourages these varieties to produce larger flowers and sturdier stems. But others claim it weakens the plants over time, causing them to need to be staked.

I recommend taking the middle road and pruning Annabelles back to between 1 and 3 feet above the soil.

PRUNING PANICLE HYDRANGEAS

Panicle hydrangeas bloom on new wood

Panicle hydrangeas also bloom on new wood. As a result, they can be pruned in late winter or early spring before they produce new growth. Cut them to the ground or to just a few feet above the soil depending on the size plant you want to maintain. The best known of the panicle hydrangeas include PeeGee and Limelight.

THE SUNNY SIDE OF LIMELIGHT HYDRANGEAS

When they were first introduced from Holland in the early 2000’s, Limelight hydrangeas took the garden world by storm. Featuring enormous, football shaped clusters of flowers, the shrubs performed great in full sun (although for best color, they require some shade).

Limelights keep their beautiful celadon color all summer long before aging slowly to pink. In the fall, they change to shades of dusty red and burgundy. They are panicle hydrangeas and they bloom on new wood. Prune them like Annabelles.

Limelight hydrangeas bloom on new wood

ENDLESS SUMMER – THE BEST OF BOTH WORLDS  

There’s a new kind of hydrangea in town called Endless Summer and it’s rocking the hydrangea world. Introduced in 2004 by Bailey Nurseries, Endless Summer hydrangeas bloom on both old and new wood. As a result, this gives them the ability to flower repeatedly all summer. The company’s tag line is, appropriately,

Experience life in full-bloom.

Endless Summer mophead variety

As of 2018, there are three different varieties currently available. Blushing Bride produces pure white mophead flowers that mature to soft pink. Twist-n-Shout is the first re-blooming lacecap variety. And BloomStruck has vivid purple or rose-pink mophead blooms that hold their color all summer. Summer Crush (available in 2019) will feature raspberry red or neon purple blooms.

It’s easy to imagine the benefits of plants that bloom on both old and new wood. Their flowers naturally last for most of the summer. Moreover, the company says Endless Summer hydrangeas bloom 10 to 12 weeks longer than average hydrangeas. Best of all, these hydrangeas need little to no pruning.

SOME COMMONLY ASKED QUESTIONS ABOUT HYDRANGEAS

Why are my hydrangea flowers turning brown in the summer?

The main reason that hydrangea flowers turn brown is too much sun; specifically hot mid-day to afternoon sun. To prevent this problem, site your shrubs in areas where they receive direct sun either in the early morning or late afternoon. Same goes for the lacecap varieties, which tend to have a much shorter flowering span than the mopheads. Attention to watering during dry spells also helps prolong blooms.

What do I do if my hydrangeas have grown too big and floppy?

Most gardeners advise waiting until the shrubs have been in the ground for 5 years before beginning a pruning program. If you’ve got the type that blooms on new wood, prune your shrubs in late winter or early spring for shape, taking them down to between 1 and 3 feet from the ground. If you’ve got the kind that blooms on old wood, follow the method above, removing 1/3 of the oldest living stalks each summer after the shrubs have flowered.

When I cut blossoms will it hurt the other blooms?

After August, cut only short stems to avoid affecting next year’s blooms

For hydrangeas that bloom on old wood, deadheading (or cutting flowers for indoor arrangements) can be performed on long or short stems in June through July without affecting next year’s flower buds. After August, it’s best to harvest only short stems.

Can I prune some of the branches without affecting the others?

Yes. You are only cutting off the flower buds on the stalks that you prune.

Does watering keep the blooms going? Why do my hydrangeas look so dry in July?

As with all plants, watering during dry spells is key. Keep the soil moist around your hydrangea shrubs to keep the flowers going all summer.

I did all the right things and my hydrangeas didn’t bloom this year. What happened?

Weather can negatively affect blooms, too

Finally, you can follow all the rules and prune your new or old wood shrubs correctly, but weather can also have its negative effects, particularly frost. In colder regions, flowering can be adversely affected by either early fall or late spring frosts, making it confusing as to whether you pruned off the blooms yourself or left it to Mother Nature.

Looking for garden ideas? I post my designs regularly on Instagram @carole.herebydesign 

 

Having A Ball With Alliums (Ornamental Onions)

Posted on by carole funger

They look like they hopped out of a Dr. Zeus book — bright purple balls stuck like lollipops on tall, sturdy stems. Ornamental onions (alliums) can be startling the first time you see them. That said, there’s so much to love about these magnificent plants, including long bloom period and resistance to most pests and diseases. And their curious appeal can really liven up a garden.

BALLS OF FUN

Why be so serious? Often it’s the unexpected that makes life so interesting. And without a doubt, ornamental onions were born to surprise. In formal landscapes, they inject a note of humor, while in informal ones they’re electrifying. And each year as their numbers grow, they form new, unexpected color combinations with other flowers in the garden.

Alliums in one of my spring gardens

Be that as it may, alliums are a relatively recent addition to the garden. In fact, they were virtually unheard of until the English garden designer Rosemary Verey, introduced them into one of her designs. Created in 1964, her jaw-dropping Laburnum Arch brought ornamental onions into the international limelight. Ever since, their popularity has only continued to grow.

Rosemary Verey’s famous Laburnum Walk

ABOUT ALLIUMS

Ornamental onions are part of the allium family, a large genus of plants that includes onions, leeks, scallions, garlic and chives. Unlike their edible cousins, however, they are cultivated solely for their flowers. Among the hundreds of species available, there are some that grow to 6 inches, while others reach as high as 4 feet. Their purple, pink or white blooms can be ball-shaped, star-shaped or pendulous. And some resemble exploding fireworks. 

Botanical Gardens in Gothenburg,Sweden/Photo: shutterstock 

Ornamental onion bulbs must be planted in the fall (at the same time as daffodils and tulips.) Most species make an appearance in late spring, when giant, paddle-shaped leaves start popping up on the soil surface. Eventually, the bulb sends up a thick, leafless stem topped by a single, swollen bud.

Over time, the bud slowly expands to reveal hundreds of tiny, star-like flowers that gradually combine to form a dense purple ball. By mid-June, many plants produce one or two additional blooms.

A fully developed flower head

DESIGNING WITH ALLIUMS

Ready to give ornamental onions a try? I say do like Rosemary Verey and go big. For the most impact, I sow my alliums in groups of threes or fives haphazardly throughout the garden. Alliums make great companions plants to other spring flowers like peonies and irises. And the later blooming varieties look great with salvia, yarrow, monarda, catmint and daylilies.

One of my designs combining alliums with pink azaleas and green hostas 

All allium varieties flower best in full sun, although they’ll also grow in semi-shade (see above.) Once the flower has died, cut the stalk down to refocus energy back into the bulb. Dried flower heads make great additions to indoor flower arrangements, by the way.

POPULAR ALLIUM VARIETIES

As I mentioned before, there are literally hundreds of allium varieties available. But, here are some of the most popular:

Purple Sensation, the earliest bloomer of all the large-flowered alliums, flowers in late spring. The variety makes a stunning companion to peonies, bearded irises and delphiniums. The 4″ to 6″ diameter violet globes float on sturdy stems that grow to 24″ high.

 ‘Purple Sensation’

If you’re looking for a big ‘wow’, try Globemaster and/or Gladiator. The tallest of the ornamental onions, these varieties boast huge purple flower heads (some measuring as big as 8″ to 10″ across) on 3 to 4-foot stems. A white version called Mount Everest is slightly shorter.

‘Globemaster’

‘Mount Everest’

Adorable Drumstick produces reddish purple cone-shaped flowers (like drumsticks) in July and is a great companion to other summer-blooming plants like daylilies, daisies, and coneflowers.

‘Drumstick’ 

Star of Persia (Allium christophii) is a wild-looking allium variety. It produces star-shaped fuchsia flowers on gray-green stems and blooms late spring to early summer.

Star of Persia/Allium Christophii

If you’re looking for real fireworks in the garden, try Schubert allium whose pink umbels look like an explosion. Seed heads look great in the garden, too, long after the blooms have faded. Blooms late spring to early summer.

Allium Schubertii

In addition to these great cultivars, there are lesser-known allium varieties that can keep the blooms going all through the summer. For more information on these as well as a great video on how to plant them, click here for Fine Gardening’s excellent article on these summer beauties.

To see photos of my garden designs, including plant lists, check out my Instagram at carole.herebydesign. I post seasonally from spring through fall. 

Aster Flowers: Your Guide To Who’s Who In The Family

Posted on by carole funger

One of the many things I love about late summer are the throngs of colorful, star-shaped flowers that pop up all over the landscape. Most of us are familiar with the yellow ones (sunflowers). But did you know that the same family also produces flowers in purple, red, pink and white? These plants are all part of the Aster family, Asteraceae, the largest and most diverse group in the plant kingdom. Continue reading →

How To Build The Perfect Monarch Butterfly Garden

Posted on by carole funger

monarch on pink flowers

Daniel Potter freely admits he’s not an expert on monarchs. But as Professor of Entomology at the University of Kentucky, he and his grad students sure love to run experiments. Recently, they completed a two-year study on the likes and dislikes of the popular orange and black butterfly. Now for the first time ever, there’s a roadmap for building the perfect monarch garden.

WHY WE CARE

If you’re reading this post, you’re probably already a monarch fan. The butterflies’ annual migration from Mexico to Canada is one of the most spectacular events worldwide. All told, the tiny insects fly upwards of 2000 miles round trip each spring, stopping four times to breed and lay their eggs. They are the only butterfly species to make such a long, two-way migration.

monarch migration

Over the past 25 years, however, there’s been a sharp decline in monarch populations. Part of this is due to a loss of habitat at the butterflies’ overwintering site in Mexico. Activities such as logging, agriculture and urbanization have all taken their toll on the central highland forests that play host to the insects six months out of every year.

But by far the most significant factor driving the decline is the dwindling supply of a plant called milkweed. The native wildflower is the only plant that monarch caterpillars will eat. And without it, the butterflies cannot complete their life cycle, sustain their migration and ultimately, perpetuate their species.

monarch feeding on milkweed

MONARCH BUTTERFLY GARDENS NEED MILKWEED 

According to the North American Monarch Conservation Plan, we need 1.8 billion milkweed stems to replace those that have been lost to agriculture and urbanization. And to sustain the annual migration, these contributions need to come from all land sectors. This includes farms, roadsides, schools, zoos and rights of way. And it also includes suburban and urban gardens located along the butterflies’ migratory corridor.

Happily, an initiative called the Monarch Waystation Program is starting to make a crucial difference. Established in 2005, it engages citizens in conservation by providing instructional materials on how to build and maintain your own monarch habitat. The guidelines are simple: Plant two or more milkweed varieties for the caterpillars to feed on along with some nectar sources for the adults, and you become part of a national registry.

To date, over 6000 Monarch Waystations in 46 states have become part of the effort. 

WHAT MONARCHS LIKE

As it happened, the Waystation Program Registry provided the perfect jumping off point for Potter’s research into monarch butterfly gardens. A quick Google Earth search by his team revealed hundreds of habitats scattered along the butterflies’ northward route. What’s more, they represented every kind of landscape.

As Potter put it, ‘Some were non-structured, others ‘wild’, and still others were surrounded by hardscape or located in open rural areas.’ Below are some aerial shots of a few of them. (Photo courtesy Dr. Daniel Potter.)

What Potter and his team wondered was this – with all of this diversity, were there certain habitats that the butterflies found more attractive than others? To find the answer, the group decided to survey 22 citizen-planted Waystations. Below are some key outcomes from their investigation. 

1. MONARCHS LIKE STRUCTURE

Like most species, monarchs use visual cues to zero in on what they’re looking for. And in the butterflies’ case, these ‘search images’ are made up exclusively of milkweed. But as the Registry revealed, not all Waystations are the same. Did monarchs favor certain monarch butterfly gardens over others?

Monarchs from ‘search images’ for milkweed

To find out, the researchers counted larvae and caterpillars for a year in their target Waystations to see if the type of habitat made any measurable difference.

monarch caterpillar on milkweed leaf

Monarch caterpillar on milkweed leaf

And they discovered that yes, the butterflies exhibited a strong preference. A structured garden, with milkweed surrounded by mulch, attracted three to five times more monarchs.

The takeaway? If you want more monarchs, make it easy for them to find the milkweed to lay their eggs on. Plant it apart from other plants. Even better, surround it with a mulch circle. But make sure to provide other nectar producing plants nearby for the returning adult butterflies to feed on.

2. MONARCHS PREFER A NORTH-SOUTH ACCESS

Interestingly, the researchers found that gardens with unimpeded north-south access recruited more monarchs. This makes sense since it coincides with the butterflies’ migratory route.

monarch migration map

Monarchs prefer gardens with a north-south access

3. THE TALLER THE BETTER

While all milkweed species are suitable for food, not all are equally favored by monarchs. To find out why, the group compared 8 varieties of milkweed all grown in Kentucky and native to the area. They evaluated them as to their suitability for egg-laying as well as their usability as food for monarch caterpillars. And there was a clear preference.

Where they had a choice, monarchs preferred the taller varieties, Swamp, Common and Showy over the smaller varieties like Butterfly weed. 

The takeaway? If you want to attract more egg-laying monarchs to your monarch butterfly garden, plant the tall, broadleaf milkweed varieties.

4. MILKWEED CULTIVARS ARE EQUALLY TASTY

But what about all of the new milkweed varieties, you might ask? As it has grown in popularity (mainly due to monarchs), milkweed is now available in many cultivars boasting unusual colors and sizes.

Asclepias Gay Butterflies Mix/White Flower Farm

Not to worry. Potter and his students discovered that monarchs find these cultivars just as attractive as the straight species. But again, go with the bigger varieties if you want more monarchs.

5. DON’T BECOME AN ECOLOGICAL TRAP

Finally, there’s the case of tropical milkweed, a non-native plant that has exploded in popularity over the past decade. Both gardeners and monarchs love it. But buyer beware. Tropical milkweed is not ‘bad’, per se, but when planted in warm areas of the U.S. it encourages monarchs to stick around longer. It even enables them to winter-breed.

tropical milkweed

Tropical milkweed, Asclepias curassavica

Research shows, however, that monarchs breeding on tropical milkweed throughout the winter (rather than returning to Mexico) have higher levels of protozoan infection compared to monarchs in the normal migratory cycles. It turns out that migration is key to outrunning these pathogens.

The takeaway? Stick to the tried and true native milkweed species and help the insects keep to their schedule.

To learn more about Daniel Potter and his research into monarchs and other insects, click here for the Dr. Daniel A. Potter Laboratory.

This article was updated January 2022.

Top Annuals for the All-Season Cutting Garden

Posted on by carole funger

Annuals for the cutting garden/Photo: Julie Hove Anderson Photography

As a landscape designer, I’m well versed in perennials and the kind of annuals you buy from a nursery. But when it comes to growing annuals from seeds, my experience lies mainly with zinnias. So recently, I was delighted to attend a webinar hosted by ButterBee Farm owner Laura Beth Resnick on the top annuals she grows for her cutting gardens. Continue reading →

Identify Plants In A Snap With These 6 Top Apps

Posted on by carole funger

 What's That Flower app

Now that we’re all spending more time at home, it can’t hurt to know what’s blooming. And finding the answer is easier than ever with one the many plant identification apps available. But which ones work best and provide the fastest, most reliable data? To find out, I decided to do a side-by-side comparison. Continue reading →

Finally, A ‘Phenomenal’ Lavender That Looks Good All Winter

Posted on by carole funger

They said it couldn’t be done, but finally, there’s a new kind of lavender that looks good all winter. Appropriately dubbed ‘Phenomenal’, it’s so good that it’s now being used for municipal plantings. To understand the hype, I purchased a few plants for a trial run. What I discovered was nothing short of, well, phenomenal. Continue reading →