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November Flowers?

After Halloween and a little before Thanksgiving, Witch-hazel (Hamemelis virginiana) starts blooming. It’s always a surprise to see its bright yellow flowers appear just as fall colors fade and branches are bare.

Witch-hazel blooming in November.

Witch-hazel is a fascinating plant. It’s a multi-trunked shrub or small tree that evolved as an understory plant in the forests of the Northeastern US. You might not notice it at all in the spring or summer when it sits modestly under bigger trees in part shade. But in early winter, when most plants are going to sleep, Witch-hazel is hard to miss. Its flowers are fragrant, and adorned with tiny yellow streamers reaching out in all directions.

Witch-hazel’s unique flowers.

The leaves, bark, and twigs of Witch-hazel contain tannins and flavonoids that Native Americans used for centuries to treat skin ailments. European colonists soon adopted the practice, and today Witch-hazel is one of the few plants the Food and Drug Administration has approved for use in over-the-counter products. Many cosmetics companies use Witch-hazel in toners, diaper rash remedies, acne treatments, pore reducers, and after-shaves.

Blooming Witch-hazel stands out against an evergreen background in winter.

A more questionable early use of Witch-hazel was the practice of using forked branches as dowsing or divining rods to search for underground water. A “water witch” would hold the forked end of a Witch-hazel branch and walk until the flexible tip supposedly dipped when underground water was detected. Dowsing with Witch-hazel branches for well-digging was a common practice right into the 20th century.

Witch-hazel flowers have nectar and sticky pollen, typical of
insect-pollinated plants.

The real mystery of this plant still isn’t settled. Why does Witch-hazel start blooming in winter when most pollinators are already hibernating? And which insects do pollinate the flowers? Some researchers have pointed to a moth species that survives freezing temperatures by shivering so hard that its body is actually warmer than surrounding air temperature. Others have suggested that a small and very late-acting bee is the pollinator. Still others have theorized that swarms of tiny gnats do the job. More research is required.

But the coolest thing about this fascinating plant? Because of its strangely late pollination, there isn’t time for the seeds to ripen in the same year the flowers open. It takes the whole next summer for seeds to slowly ripen in their pod. Then, just as the flowers start blooming again in the freezing cold, the pod explodes throwing ripe seeds 10 to 20 feet away, where they will rest until spring weather is warm enough for germination. It’s a risky reproduction strategy, but it seems to work well for this native plant.

Seed pod almost ready to pop.

Witch-hazel is an easy choice for smaller properties. As a multi-trunked tree or shrub, it rarely exceeds 20 feet in height. It is an understory plant, so it does well in part shade under mature trees, but is also happy with more sun. It is winter-hardy in Zones 3 to 8, and is not fussy about soil, but average moisture and a covering of leaf litter throughout the season is recommended. No special care is required and Witch-hazel rarely needs pruning. In summer, it is an open, airy plant with medium green leaves, but in fall, the leaves turn apricot gold before dropping just as the crazy flowers start to open. The flower show typically lasts a month or more.

Hamemelis virginiana is an easy choice for suburban landscapes.

Lately, we’ve seen nurseries offering non-native hybrids of Witch-hazel for sale. These varieties with orange or red flowers are recent introductions of hybridized Asian species, so their value to our native wildlife and potential for invasiveness are unknown. Our view is that it’s always safer to go with species that evolved in our region.

Witch-hazel contrasts with Winterberry (Ilex verticillata).

Hamemelis virginiana, our native Witch-hazel, is a garden-worthy plant that brings late-season interest to suburban landscapes. Try it against a background of evergreens or with berry- producing shrubs. On a cold winter’s day, you won’t be sorry.

THIS BLOG IS WRITTEN BY CATHY LUDDEN, CONSERVATIONIST AND NATIVE PLANT EDUCATOR; AND BOARD MEMBER, GREENBURGH NATURE CENTER. FOLLOW CATHY ON INSTAGRAM FOR MORE PHOTOS AND GARDENING TIPS @CATHYLUDDEN.

Stocking Up

Despite sunny warm days in October, many of our wildlife friends know that time is short.

So, they are busy stocking up for the long winter ahead. Native bumblebees are storing pollen and nectar to provision their underground nests for hibernation. Migrating butterflies and hummingbirds are hunting for nectar along their routes as they travel to tropical regions. Songbirds are loading up on seeds and berries before continuing on to their winter homes.

Monarch butterfly stocking up in October before heading south.

At this critical time of year, it is up to us to provide nutritious food that birds, bees, and butterflies need. Suburban yards can, and should, provide the necessary resources.

The good news is that the best plants for supporting wildlife are also the best plants for adding fabulous fall color to your landscape! You can fill your yard with long bloomers, late bloomers, and seed and berry producing plants that will make you a fall hero both to wildlife and to your neighbors!

A lovely place to stock up!

Long bloomers:
Two of the best fall plants for native bees actually start blooming in early to mid-summer and don’t stop until the first frost: Anise Hyssop (Agastache foeniculum) and Mountain Mint (Pycnanthemum muticum). It’s hard to think of any garden plants that do so much for so long. Both of these native perennials attract a huge variety of pollinators all summer, and both somehow manage to keep producing nectar well into fall. They are garden show-offs and very easy to grow. Perfect for pollinator gardens, both plants do best in full sun, are drought tolerant, and are completely ignored by deer, rabbits, and woodchucks. Now, in mid-October, they are still covered with bumblebees, honey bees, skipper butterflies, and dozens of small pollinators all stocking up for winter. See earlier blog posts for more info on Anise Hyssop here, and on Mountain Mint here.

Anise Hyssop in July.
Still supplying nectar in October.
Mountain Mint in July.
Mountain Mint in October.

Late bloomers:
The most iconic native flowers of fall are Goldenrod and Asters. Goldenrod is a keystone plant, meaning many species of insects need it to survive. More than 20 species of native bees, for example, can eat only the pollen of Goldenrod, so they go looking for it to provision their nests.

Goldenrod is critical food for many pollinators.

While some goldenrod species can be too aggressive for suburban gardens, cultivars like Solidago rugosa ‘Fireworks’ and Solidago sphacelata ‘Golden Fleece’ are well-behaved and make beautiful additions to the autumn landscape. For more on Goldenrod, click here.

Solidago ‘Fireworks’
Solidago ‘Golden Fleece’

Asters are also keystone species, and they are pollinator favorites. Unfortunately, many of them are also favorites of deer and rabbits. So, while New York Aster and New England Aster are incredibly valuable in protected areas, if your yard is browsed by deer, White Wood Aster and Aromatic Aster, are the best bets.

White Wood Aster blooming in October.

White Wood Aster (Eurybia divericata) is native to the forests and shady woodlands of the Northeast, and is a great choice for underplanting trees and shrubs. As one of those rare plants that thrives in dry shade, it is an excellent native substitute for pachysandra, ivy, or vinca. It starts blooming in late September or early October and continues into November with small daisy-like flowers with yellow centers. In a fascinating trick that helps late-season pollinators save energy, the yellow flower centers turn a burgundy color after they are pollinated, so bees know not to waste their time looking for pollen where it’s already been harvested! Growing 2 to 4 feet high, but shorter and fuller in part sun, White Wood Aster seeds itself around freely without becoming a nuisance. Blue Wood Aster (Symphyotrichum cordifolium) is equally beautiful and equally useful in similar garden situations.

White Wood Aster in a part-shade garden setting.

Aromatic Aster (Symphyotrichum oblongifolium) is native to much of the Southeastern and Central US, but is hardy in Zones 3-8, well north of its native range. It prefers sunny, dry areas with relatively poor soil, and is a good companion for ornamental grasses. Aromatic Aster forms a bushy clump and looks great massed where its flower impact is really spectacular. Plants grow 2 to 3 feet tall and form a densely-branched, mounded shape with small dark green leaves. It blooms profusely in October, completely covering itself with one-inch purple or lavender flowers loved by late-season native bees and butterflies.

Aromatic Aster ‘Raydon’s Favorite’ puts on a dazzling October display.

Seed and Berry Producers:
Migrating birds, as well as birds that stay through the winter, need nutrient-rich berries and seeds to build strength for the challenges ahead. The seeds of coneflowers and black-eyed Susans nourish goldfinches.

Photo: Montclaire High School blog 2017

Research has shown that the fruits of non-native invasive plants such as Korean dogwood, porcelain berry, burning bush, and barberry are less nutritious for North American birds than the fruit of native plants. Invasive berries are low in fat and protein and high in carbohydrates, which reduces their nutritional value. It makes sense that the healthiest plants for native birds are the plants that co-evolved with them.

A yellow-rumped warbler grabs a berry from Common Juniper.
Photo: Saverio DiGiorgio @Savwildlifephotography

Beginning in late summer, many of our native trees and shrubs produce berries and seeds that birds need. Happily, these plants also produce the best fall show in our landscapes! It is an absolute joy to watch birds harvest seeds and berries as they travel through brilliant fall foliage in suburban yards.

The native Possumhaw viburnum (Viburnum nudum) has nutritious berries birds love.

Many native trees and shrubs, including Crabapples, Winterberries, Chokeberries, American Hollies, Hawthorns, and American Dogwoods, supply berries for wildlife and gorgeous fall color for us. These plants are great choices for Northeastern suburban yards.

American Cranberrybush (Viburnum trilobum) and Chokeberry (Aronia melanocarpa)
provide berries and dazzling fall color.
The fruit of Crabapples begins ripening in the fall.
Hawthorn trees (Crataegus ‘Winter King’) also produce colorful and nutritious fruit.

And don’t forget the squirrels! They need to stock up for winter, too. Just watch this happy grey squirrel in an American Dogwood (Cornus florida)!

So, make your yard a grocery store for winter wildlife! It’s not too late for planting trees, shrubs, and hardy perennials. Think about adding a few of these plants now to make your yard a healthy — and colorful — place for butterflies, bees, and birds for many autumns to come.

THIS BLOG IS WRITTEN BY CATHY LUDDEN, CONSERVATIONIST AND NATIVE PLANT EDUCATOR; AND BOARD MEMBER, GREENBURGH NATURE CENTER. FOLLOW CATHY ON INSTAGRAM FOR MORE PHOTOS AND GARDENING TIPS @CATHYLUDDEN.

Where Do Fireflies Sleep?

Although we only see them in summer, autumn is a critical time of year in the life of these magical creatures. What we do in our landscapes in the fall determines the health and well-being of the firefly population for the following summer.

There are more than 150 species of fireflies in North America. In the Northeast, the most common are in the Photinus group, which includes about 15 different species. To find their own species in the dark, fireflies have adapted a highly specialized method of communication. The blinking light display that so charms humans is part of the firefly mating ritual!

Photinus pryalis is about half an inch long and emits a yellow-green flashing light.

Each species of firefly has its own distinctive flash pattern, like a message in Morse code, to signal potential mates. Depending upon the species, flashes may be single or in multiples, short or long, and spaced at specific intervals. The characteristic pattern helps each species find its mates. The males fly around blinking their distinctive pattern. Females rest on the ground, or on low vegetation, and answer by flashing back at the right time. In this way, the female chooses her mate – if she doesn’t flash back to a passing male, he can’t find her in the dark!

Fireflies are beetles with wings hidden under a hard shell.

The flashing light, or bioluminescence, is caused by a chemical reaction in the insect’s lower abdomen, and varies in color from species to species. The “lantern” on the male is larger than on the female, usually covering two segments of the body rather than just one in females.

The blinking part of a firefly is the lower abdomen.

Because fireflies use their flashing light pattern to find mates, outdoor landscape lighting can be a big problem. Darkness is necessary for fireflies to find their mates, and artificial lights confuse them, interfering with the ancient mating ritual. So, you can help just by adjusting your yard lights to be sure it’s dark when fireflies are active in summer. Use only motion-activated lights, or low-wattage yellow or red lights, and use timers to turn lights off completely at the earliest hour possible. Not only does a dark yard help fireflies find mates, it also makes their magical display easier for you to see and enjoy.

So, after a romantic night, where do fireflies sleep?

Adult fireflies spend daylight hours resting at ground level in vegetation where there is humidity and cover. At dusk, you can see them rise up from the low vegetation and drift higher as the sky darkens. A few days after mating, the female lays fertilized eggs on or just under the surface of the ground in the same damp areas where she has been hiding during the day.

An adult firefly resting on butterfly milkweed.

So, ground and soil conditions are critical for firefly populations. Avoid disturbing the ground by mowing, or using high-powered leaf blowers, or spraying pesticide. If the female firefly finds a good spot, under trees or shrubs, or in a patch of native perennials, in tall grass, in leaf litter, or under a loose brush pile where her eggs won’t be disturbed, then the eggs will hatch in two to four weeks, emerging as hungry larvae.

Firefly larvae need a damp, undisturbed habitat where they can
find and feed on multiple garden pests.
Photo: Ken Johnson, University of Illinois Extension

Firefly larvae don’t look anything at all like the adults we recognize, (though the larvae do glow in the dark!). The larvae feed until the end of summer on soft-bodied insects, including slugs, snails, worms, other garden pests, and even mosquitos — which makes fireflies extremely beneficial insects! Then in the fall, the larvae must find a safe place to hibernate for the winter.

And that is why our fall landscape practices are critical. If we insist on keeping very tidy yards, where every fallen leaf has been blown and bagged for removal, future fireflies hiding as larvae in the leaf litter, or in soil protected by those leaves, will be lost. If we cut our flower beds to the ground and send away the dead stems and leaves, not only fireflies, but also many species of butterflies, moths, and native bees will be doomed with no safe place to hibernate for the winter. Cutting ornamental grasses to the ground, and mowing lawns short before winter, also dries out the damp ground where firefly larvae hibernate, reducing their chances of surviving until spring.

Leaf litter and uncut flower beds protect firefly larvae until spring.

If firefly larvae overwinter safely, and are not destroyed by overly-aggressive spring garden clean-ups, they will emerge hungry and ready to hunt various garden pests well into summer, when they finally pupate, becoming adult fireflies. If allowed to mature in safe habitat, fireflies will again delight children of all ages when summer arrives.

Fireflies introduce children to the wonders of nature.
Photo: Bernheim Forest and Arboretum

Though catching fireflies may be one of the chief joys of childhood, it is best to use a net to avoid hurting the insects’ soft bodies. Don’t squeeze their abdomens, and be sure there is no insect repellant on your hands. You can put fireflies in a jar for an hour or two to observe them more closely, but add a bit of wet paper towel to keep the humidity up, and be sure to release them where you found them well before morning. They will not survive long in captivity.

Firefly populations are decreasing across the US, but you can help by following many of the same practices that protect pollinators:

  • Provide safe habitat by planting trees, shrubs, grasses, and flowering perennials in parts of your yard, and allowing leaves and dead vegetation to stay there – especially over winter and into spring.
  • Do not use pesticide on lawns, and avoid poisons meant for slugs and snails. Do not spray for ticks or mosquitos under shrubs and trees where fireflies hide. So-called “natural” and “organic” insecticides are still lethal for fireflies, butterflies, moths, and bees.
  • Reduce or eliminate unnecessary outdoor lighting during the summer when fireflies and moths are active. Use motion-activated lights or timers, and aim lights downward wherever possible.

By taking these simple steps, we can protect the magic of fireflies on sultry summer nights for many generations to come.

Photo: Judd Patterson @Juddpatterson.com
THIS BLOG IS WRITTEN BY CATHY LUDDEN, CONSERVATIONIST AND NATIVE PLANT EDUCATOR; AND BOARD MEMBER, GREENBURGH NATURE CENTER. FOLLOW CATHY ON INSTAGRAM FOR MORE PHOTOS AND GARDENING TIPS @CATHYLUDDEN.

What is it Worth?

Most Baby Boomers will recall a wild outdoor place somewhere near where they grew up: a patch of woods, a pond, a swamp, or maybe an open grassy field where fireflies congregated at dusk. Days spent catching frogs, finding salamanders, maybe spotting a garter snake or a turtle, and definitely seeing lots of monarch butterflies, were all part of what made childhood summers so magical.

Where the wild things are…

But if you ask those same Boomers what happened to the wild places in their old neighborhoods, chances are they will say, “long gone” – lost to development.

Before World War II, just 13% of Americans lived in suburbs. By 2010, however, suburbia was home to more than half of the US population! Inevitably, corporate offices, shopping malls, warehouses, schools, sports facilities, local government offices, and the roads, parking lots, and altered landscapes servicing this vast migration, eliminated the undeveloped “wild” places of childhood memories.

Today we are warned that our kids are suffering from “nature deficit disorder.” We hear that the average 5th grader can identify hundreds of corporate logos, but only two or three species of plants, including common trees. And it is shocking how many kids are terrified of completely harmless insects and animals because they’ve had no interaction with them. Suburban adults are often part of the problem: worried about mosquitos and ticks, they spray pesticides that wipe out fireflies, butterflies, bees, and any other insects that might provide food for birds — or learning experiences for children. The resulting sterilized landscape offers little opportunity for discovery of nature.

Sterile suburban landscape
Suburban yards are routinely treated with toxins

But if you are lucky, there may be a good local nature center where you can find the cure for nature deficit disorder.

Greenburgh Nature Center

The Greenburgh Nature Center is such a place. Surrounded by suburban homes, schools, golf courses, and a busy commercial corridor, the 33-acre grounds of the Nature Center offer forest, meadow, and wetland habitats where birds, butterflies, bees, and countless species of insects and small animals can be observed in nature.

Inspiring a love of nature

Visitors are free to wander and observe on their own, and children make eye-opening discoveries every day at the Nature Center. Highly-educated and skilled naturalists on staff offer insights and interesting information to children and adults about animal behavior, ecology, native plants, and the historical use of the Nature Center’s land by indigenous peoples.

Naturalist with visitors

For fifty years, the Greenburgh Nature Center has been a model public/private partnership inspiring a passion for nature and enhancing the quality of life in its community. The “public” part of the partnership is the site: a protected piece of land and a 100-year-old Manor House acquired by the Town of Greenburgh with funding help from the State of New York.

The “private” part of the partnership is a 501(c)(3) non-profit educational organization called “Nunataks, Ltd.” that provides all of the programs and services at the Nature Center. Nunataks employs the staff naturalists, who with degrees and experience in multiple nature-education disciplines, run school programs, day camps, after-school activities, birthday parties, animal husbandry experiences, and seasonal nature events for the whole community.

Naturalist explaining seasonal seed dispersal

For 50 years, this public/private partnership has been incredibly successful! The Nature Center welcomes over 100,000 visitors annually and runs programs for over 12,000 students each year from multiple area communities. Outdoor experiences on site include forest trails, a native-plant meadow with a live butterfly exhibit, native plant gardens, a vernal pond, a playground, a barnyard with farm animals, beehives, and a replica Native American wigwam and long house with educational exhibits about indigenous peoples.

Day camp butterfly study

Indoors, visitors can meet numerous live animals from mammal, reptile, amphibian, aquatic, and avian species tended by trained volunteers and naturalists who explain their characteristics and supervise their careful handling by visitors. There are also science displays, and event spaces for programs, birthday parties, educational crafts, and adult classes. All of these experiences are provided on site by Nunataks, Ltd., the educational non-profit organization.

Adults attending a native plant meadow tour

Sadly, this incredible community resource is now threatened by a breakdown in the public/private partnership that has served the community so well. The Town of Greenburgh has balked at renewing its contract with the non-profit Nunataks, Ltd. to continue operation of the Nature Center. Under the terms of the existing 25-year contract, the Town currently pays Nunataks, Ltd a fee that covers less than 20% of costs of operating the Nature Center. The remaining 80% of the Nature Center’s expenses are covered by membership fees, grants, donations from individual community members, and revenues from programs run by the non-profit staff. The amount currently paid by the Town of Greenburgh is no more than ¼ of 1% of Town’s annual budget. The Town Board, however, has declined to renew the contract at that minimal cost. If the contract is not renewed, the Greenburgh Nature Center must cease operation.

What is the value of the Nature Center to the community?

What is the benefit of hands-on nature education in an oasis of wild space for families surrounded by manicured landscapes and pavement? What does it mean to a child to see a butterfly emerge from a chrysalis? What is it worth to teenagers to discover that complex plant/animal relationships in nature are real and visible and not confined to textbooks? What is the benefit of a few quiet moments of bird-watching in a wildflower meadow?

If you value these things, please help us by signing the petition below. If you are part of our community, please contact the Greenburgh Town Supervisor and members of the Town Board urging them to renew the Nature Center’s contract.

What is the value of a moment in nature?

And if you live in another community and are lucky enough to have a resource like our Nature Center, do whatever you can to support it and preserve the value of nature education in a patch of wild space. We all thank you.

Click here to sign the petition.

THIS BLOG IS WRITTEN BY CATHY LUDDEN, CONSERVATIONIST AND NATIVE PLANT EDUCATOR; AND BOARD MEMBER, GREENBURGH NATURE CENTER. FOLLOW CATHY ON INSTAGRAM FOR MORE PHOTOS AND GARDENING TIPS @CATHYLUDDEN.

The Shape of Hydrangeas

It’s hydrangea season and they are everywhere! But where are the bees?

Have you noticed that bees happily buzz around some hydrangeas while ignoring others? The difference is striking with these two hydrangea shrubs seen blooming side-by-side:

What accounts for the difference?

You might reasonably guess that native hydrangeas would be more attractive to native bees than Asian varieties, because that is often the case with other plants. Insects in North America usually prefer the plants with which they co-evolved, so non-native species are much less useful to them. But in the video above, both shrubs are non-native hydrangea varieties. So, what’s the difference to the bees?

When it comes to hydrangeas, it’s the shape of the flower that matters – at least to bees! And since 25% of native bee species are in sharp population decline, we really must care about what’s important to bees.

Hydrangea flowers, properly called “panicles,” are typically one of three shapes: “mophead,” “lace-cap,” or “conical” (cone-shaped).

Mophead
Lace-cap
Conical

In nature, hydrangeas have either lace-cap or conical forms composed of many tiny fertile flowers accompanied by larger showy 4-petaled flowers that are sterile. The only purpose of the sterile flowers is to attract the attention of pollinators, directing them to the real flowers – the tiny ones loaded with pollen and nectar.

Large sterile flowers draw attention to the tiny fertile
flowers inside
Pollinators find nectar and pollen in the fertile flowers

For bees, the sterile flowers on hydrangeas are just advertising. For humans, the sterile flowers are the pretty part. So, for hundreds of years, humans have been manipulating hydrangeas with selective breeding and genetic modification to create panicles with more showy sterile flowers and fewer — or zero — fertile flowers. The heavily-modified hydrangeas are spectacular to human eyes, but useless to pollinators.

Some of the showiest mophead hydrangeas have no
fertile flowers at all, and produce no pollen or nectar

The intentional modification of hydrangea flowers has crossed continents and hydrangea species. Many of the most popular hydrangeas in gardens today are mophead versions developed from the Asian species, Hydrangea macrophylla, or big-leaf hydrangea. You recognize these as the big round flowers that are pink or blue depending on the acidity of the soil, but they are also available in white, pale green, hot pink, and other colors. In fact, there are countless varieties of heavily-modified Asian hydrangea species on the market, including the popular tree form “Pee Gee” and the enormous conical flowers of “Limelight,” both modifications of the Asian Hydrangea paniculata.

Native North American species have been similarly modified to create fancy flowers. Hydrangea arborescens, or Smooth Hydrangea, is native to forests from New York to Ohio, and south from Oklahoma to Georgia. In the wild, it has flat-topped clusters of tiny white fertile flowers with occasional mutations adding a few sterile flowers scattered around the outer ring.

Natural form of the native Hydrangea arborescens

To make its flowers more appealing to humans, growers selected the mutated flowers and modified them dramatically to increase their number and size, eventually eliminating the fertile flowers altogether. The result was a plant with enormous mophead flowers that they labelled ‘Annabelle’ hydrangea, and introduced to the American market in the 1960’s. Since then, many other named varieties (‘Snowball,’ ‘Incrediball,’ ‘Invincibelle,’ etc.) have been developed to appeal to gardeners. Unfortunately, these showy mophead forms offer nothing to bees because the fertile flowers have been manipulated out of existence.

‘Annabelle’ and other cultivars of Smooth Hydrangea
have made this native plant useless for bees.
Photo from nursery advertisement

Even our excellent native shrub, Oakleaf Hydrangea (Hydrangea quercifolia), has been targeted for flower modifications by growers. Oakleaf Hydrangea naturally has large conical flowers that emerge white and gradually turn pink. They are beautiful and loaded with fertile flowers that are an important source of nectar and pollen for bees. (For more information on Oakleaf Hydrangea, click here.)

Oakleaf Hydrangea is native to the Southeastern US,
but grows well in gardens throughout the mid-Atlantic region
Conical flowers of Oakleaf Hydrangea are beloved by bees

Apparently not satisfied with an already excellent and garden-worthy native plant, the nursery industry has introduced cultivars of Oakleaf Hydrangea with flowers so altered that they have no remaining value to bees.

A double-flowered version of native Oakleaf Hydrangea
has eliminated fertile flowers completely
Dense conical flowers with no interior fertile flowers on
this Asian hydrangea do not support bees

Open conical flowers with large clusters of fertile flowers inside, like natural Oakleaf Hydrangea flowers, are a feast for bumblebees and other pollinators. And lace-cap flowers, whether Asian or native, because they are formed with large clusters of fertile flowers in the center, attract many species of bees.

An Asian lace-cap hydrangea visited by bumblebees

In a recent 5-year trial at the Mt. Cuba Center in Delaware, 29 cultivars of the native Smooth Hydrangea, including 16 mophead and 13 lace-cap varieties, were evaluated for garden appeal and performance. https://mtcubacenter.org/lacecap-hydrangeas-take-top-marks/ Investigators also monitored each of the plants for pollinator visits, extrapolating the results over the growing season. They found that lace-cap flowers were visited by pollinators at 3½ times the rate of mophead flowers. Although they did not report on the duration of visits, they did observe that bees approached the mophead flowers, but apparently did not often find reason to stay.

So, if we care about bees, flower shape matters!

For gardeners who love hydrangeas and also care about bees, the best bet is to include lace-cap and open conical flower forms with plenty of fertile flowers in your garden. Native Oakleaf Hydrangeas in natural form and native Smooth Hydrangeas in lace-cap form (like ‘Haas’ Halo’) are widely available at nurseries. And if you love the bright colors and playful shapes of the Asian lace-caps, they are a much better choice than the mopheads.

Go ahead and enjoy your mophead hydrangeas – they are harmless and we all love them. But think about adding a few lace-caps or conical forms with lots of fertile flowers for our bee friends.

You’ll love them, too!

THIS BLOG IS WRITTEN BY CATHY LUDDEN, CONSERVATIONIST AND NATIVE PLANT EDUCATOR; AND BOARD MEMBER, GREENBURGH NATURE CENTER. FOLLOW CATHY ON INSTAGRAM FOR MORE PHOTOS AND GARDENING TIPS @CATHYLUDDEN.