pollinator plants Archives - Page 3 of 5 - Nature Center at Greenburgh

July 15, 2022February 13, 2025 Cathy Ludden Around the Grounds, Native Plants

Summer Buzzin’

Have you ever heard a plant hum?

On a sunny summer day, you can actually hear Shrubby St. John’s Wort humming. It’s not the plant itself, of course, but the sound of extremely happy bumblebees buzzing as they collect pollen from countless bright yellow pom-pom flowers.

“St. John’s wort” is the common name for a family of almost 500 plant species worldwide. The name refers to its time of bloom – around St. John’s Day on the Christian calendar, or June 24. “Wort” is the old English word for “plant,” especially plants known for their medicinal value. Perhaps you’ve heard St. John’s wort recommended as an herbal remedy for mild depression? That particular St. John’s wort is Hypericum perforatum, a weedy perennial native to Europe and now considered invasive in parts of North America.

**Shrubby St. John’s Wort in front of the Manor House**

The “humming” plant we love is Hypericum prolificum, or Shrubby St. John’s Wort. It is a beautiful shrub, native to the US from New York west to Minnesota and south to Louisiana and Georgia. It does indeed start blooming at the end of June, and continues to dazzle for weeks into the summer. The scientific name “prolificum” refers to the enormous number of flowers the shrub produces. The shrub itself forms a rounded mound 3 to 4 feet tall and wide with small blue-green leaves.

**Shrubby St. John’s Wort loaded with flowers**

If you go shopping for Shrubby St. John’s Wort, you will likely see Hypericum frondosum, a very similar shrub with a cultivar called “Sunburst” that has slightly larger flowers. Its original native range is further south, in Tennessee and Kentucky, but it does perfectly well in southern New York gardens and throughout Zones 5 to 8. Another species, Hypericum kalmianum, is native to the Great Lakes region and hardy to Zone 4. While botanists can tell these three shrubs apart, most gardeners consider them virtually interchangeable. And all of them have year-round value as landscape plants.

Shrubby St. John’s Wort is essentially carefree, and makes an attractive foundation plant or hedge in full sun. It doesn’t need pruning, but you can shape it to suit your site. The leaves produce a substance that is mildly toxic to deer, so deer avoid it. In autumn, the shrub holds onto its leaves until late in the season, and it has great fall color. And in winter, interesting seed capsules remain on branches that have attractive grey-brown bark.

**Fall color is a mix of red, yellow, and orange**

There is no nectar in the flowers of St. John’s Wort, so it’s not a stopping place for butterflies. However, caterpillars of several moth and butterfly species, including the lovely gray hairstreak butterfly, do use the leaves as a host plant. Pollen is the big attraction. The flowers have a huge number of stamens, all loaded with pollen, so bees of every size and description come to the party.

**How many bumbles can you find on just 3 flowers?** **(Hint: there are 5!)**

We never get tired of watching the action, and we can observe up close because the bees won’t spare a second even to notice nearby humans. They are fixated on pollen collection, as you can see in this slow-motion video:

Pollen collection

And what about that summer buzzin’? Turn your sound up and, technology permitting, you may hear the sound of a plant humming!

Summer buzzin’

THIS BLOG IS AUTHORED WEEKLY 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.

June 16, 2022February 13, 2025 Cathy Ludden Around the Grounds, Pollinators

Happy Pollinator Month!

June is here — the bees are buzzing, the butterflies are fluttering, and everybody is excited about summer flowers. It’s National Pollinator Month!

At the Nature Center, we are also celebrating the first anniversary of our newest Pollinator Garden. It is astonishing to see how lush, diverse, and colorful our garden has grown in just one year!

Want to know how we did it?

Right next to our big open lawn, in a very visible spot near the beehives, there was a messy patch of weeds. The soil was poor and dry, and there was very little shade. So…the perfect spot for a pollinator garden! The first task, done by Guy Pardee of Suburban Natives LLC, was to clear the area, getting rid of all the weedy invasive plants. Then, the ground was covered with leaves and left for the winter.

The following spring, we cleared it again and prepared to plant.

A good friend to the Nature Center, Bill Boyce of Biosphere Landscape Architects, came up with a great idea for the garden. We would make a literal “pollinator pathway” wandering through the blooming flowers, with signs along the way identifying pollinators. Bill did a “back-of-the-envelope” concept sketch for us on site.

We roughed out the lines in the dirt, and then defined the path with mulch.

Then it was time to plant. We chose tough native plants — species that evolved in our region growing in open dry meadows, able to survive without fertilizer, pesticide, or supplemental water. And though we planned to water and weed the garden for a season or two until the plants were established, we wanted a garden that eventually would need little maintenance. We also needed plants that would not be attractive to deer, rabbits, or woodchucks. We made a plant list, scoured the nurseries, and bought about 450 plants in containers (with funds contributed by multiple donors).

If you would like to know which plants we selected, click on the link below.

Plants-in-the-Pollinator-Garden-at-the-Greenburgh-Nature-Center Download

We started in the middle, planting the “spine” of the garden with tall, deep-rooted Switch Grasses that would support the tallest flowers in the center of the garden.

**The center “spine” of the Pollinator Garden**

We then worked outward, planting clusters of flowering species arranged in descending height. Shorter native grasses and ground covers were added along the edges to fill in and provide texture. We planted densely, aiming to have the plants grow together to occupy all soil areas within 2 seasons, thereby reducing available space for weeds.

**Plants are spaced 12 – 18 inches apart**

We decided not to mulch after planting, for a few reasons. Some of the invasive plants removed from the area were deep-rooted and would re-appear soon, with or without mulch. Weeds would be easier to see and remove promptly if we did not mulch. We also hoped our new plants would quickly grow together, expanding to occupy the entire ground space, and reseed themselves freely in the garden. Mulch would inhibit those natural growth processes. Finally, mulch would prevent the pollinators we are trying to attract from nesting in the ground, as many of them want to do. We want to support pollinators through their entire life-cycles.

We finished planting the Pollinator Garden on June 2, 2021. By August 2, it was in full bloom and alive with pollinators.

**Two months after planting, August 2021**

As we had hoped, this spring the garden came back full and lush. Weeding is ongoing, but not as difficult as we had anticipated.

**The Pollinator Garden this week, June 2022**
Photo: Nick Macaluso

So, please come celebrate Pollinator Month with a walk on our new pathway, and let the pollinators give you a tour!

THIS BLOG IS AUTHORED WEEKLY 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.

March 24, 2022February 14, 2025 Cathy Ludden Around the Grounds, Native Plants

What’s the Buzz?

Have you heard all the “buzz” about pollinator gardens? It seems that community groups everywhere are planning, planting, or maintaining pollinator gardens. Schools, parks, churches, and homeowners are adding pollinator-friendly native plants to landscapes all around us. Are you involved?

The original “Pollinator Pathway” idea was to create linked gardens through urban and suburban areas so that pollinators could travel, finding what they need to survive along the way.

The concept has grown wildly and Pollinator Pathway organizations are popping up everywhere, including locally in Irvington, Hastings-on-Hudson, Dobbs Ferry, Bedford, Elmsford, and many others.

Physically connecting pollinator gardens into an actual pathway is less important than having lots of them everywhere. From big meadows to front lawn patches to container gardens on balconies, every blooming native plant helps pollinators.

**August Brosnahan and friends started a pollinator garden along the Old Croton Aqueduct**

**Friends of Dobbs Ferry Waterfront Park planted native plants for pollinators**
*Photo: Don Vitagliano*

Driving this movement is recent documentation of a stunning decline in insect populations, especially pollinators. Since many of our food crops depend on insect pollination, this is a huge wake-up call for all of us. Insecticides, agricultural techniques, and loss of habitat all contribute to crashing insect populations. And since most birds depend upon insects to feed their young, bird populations also are declining rapidly.

**The New York Times reports on the “Insect Apocalypse”**

Unlike many other global problems, we can actually do something about this crisis — right in our own yards. Pollinator gardens are a powerful force for good. And the bonus? They are gorgeous! Every time we convert a patch of lawn, or bare dirt, or a weed-infested spot to a pollinator garden, we not only provide survival essentials for birds, bees, and butterflies, we brighten our neighborhoods with color and life.

**The pollinator garden at Dobbs Ferry Waterfront Park**
*Photo: Nancy Delmerico*

**This pollinator garden replaced a lawn in Hastings**
*Photo: Myriam Beck*

So, what makes a garden a pollinator garden? Short answer: native flowering plants. The two main classes of pollinators we are trying to save are butterflies and bees, especially native bees. Bees need flower nectar and pollen. Butterflies need nectar and host plants for their caterpillars to eat. Pollinator gardens should provide all 3 essentials: nectar, pollen, and host plants.

**Native bumblebees need pollen from native plants**
*Photo: Travis Brady*

The reason we keep emphasizing native plants is because most of these insects are specialists — they depend upon one or two specific species of plants for survival. For example, there are over 20 species of native bees that can only eat the pollen of Goldenrod! And just as Monarch caterpillars can only eat the leaves of Milkweed, other butterflies’ caterpillars are also completely dependent upon specific plant species – their “host”plants.

**Swallowtail butterfly caterpillar on its host plant, Zizia**

**Adult Black Swallowtail on Zizia at the Nature Center**

Pollinator gardens do best in sunny spots. Butterflies and bees prefer sunshine and are more active in sunny areas. Any place that lawn grass grows is a good spot for a pollinator garden.

The best plants for pollinator gardens are native meadow or prairie plants. Adapted to harsh environments, they don’t need rich soil and never need fertilizer. Most of these plants are drought-tolerant, so they don’t need irrigation once they are established, and many are deer-resistant. And we recommend perennials rather than annuals, so the plants come back every year. It is easier, and definitely cheaper in the long run, to plant a perennial pollinator garden than it is to buy, plant, water, and fertilize annual bedding plants every year.

**Pollinator Garden at the Nature Center**

Spring is almost here! If you are thinking about planting or expanding a pollinator garden, there are loads of great resources to get you started. The Pollinator Pathway website linked above has how-to’s and plant lists. Watch for local native plant sales. The Native Plant Center will hold its annual plant sale this year at Westchester Community College on April 30. And the Garden Club of Irvington will have native plants for sale at the Greenburgh Nature Center on May 7, plus lots of knowledgeable help on hand.

And watch this space! Over the next several months, this blog will highlight many of our favorite pollinator plants. Come see them in action at the Greenburgh Nature Center all season long!

THIS BLOG IS AUTHORED WEEKLY 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.

February 23, 2022February 14, 2025 Cathy Ludden Around the Grounds, Native Plants

Barking Up the Right Tree

If you were a hungry bird looking for a high-protein snack in mid-winter, where would you go to find some tasty insects? And if you are a human desperate for something interesting to look at in the mid-winter landscape, what would you like to see out your window or along a path? To answer both questions, take a look at the gorgeous bark of our native River Birch (Betula nigra).

River Birch is a great tree for landscapes in our area. As the name implies, its native habitat is stream-side or near a pond. But it is perfectly happy in our acidic soil with average moisture. We have it planted next to the Meadow at the Nature Center, without any irrigation at all, and it is doing fine. It is also perfect in an area that floods occasionally, as long as the soil dries out in a few days, and there is plenty of sun.

Young River Birches at the edge of the Nature Center’s Meadow

River Birch can be a single-trunk tree, but it is more commonly multi-trunked, which adds some interesting variety to residential plantings. It is fast growing – over two feet per year – and can reach 50 to 70 feet ultimately. It does not pose a risk to houses or other structures, but it will drop lots of small twigs after a wind storm. River Birch has small glossy leaves that move lightly in the breeze and provided dappled shade. Fall color is golden yellow and lasts for weeks.

A gorgeous stand of River Birches pond side – *Photo courtesy of Mia Edwards*

Birch trees are one of the most valuable host species for butterflies and moths, providing the critical food source for 413 species of Lepidoptera (butterfly and moth family). And that means birds will flock to your River Birch all summer to find caterpillars to feed their chicks. A birch grove is a bird sanctuary all summer with lots of food and hiding places. And in the winter, woodpeckers, nuthatches, chickadees, and many other birds will hunt in the millions of folds and crevices in the bark for over-wintering insects.

A close look at the bark reveals a food pantry for birds

Can you see where the woodpeckers have been hunting?

As River Birch matures, the bark becomes less flaky on the lower trunks, but the upper branches retain that cinnamon color and peeling texture. Don’t underestimate the ultimate size when you plant River Birch. After 20 years or so, each trunk can reach over a foot in diameter, so a multi-trunked tree will need some room.

But what a pleasure that bark is in the winter landscape!

A 20-year old River Birch shows off its “winter interest”

This blog is authored weekly 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.

February 10, 2022February 14, 2025 Cathy Ludden Around the Grounds, Native Plants

Forever Green: Native Groundcovers That Stay All Winter

Given our recent weather, you may well ask, “why should I care whether a ground cover is green if it’s under a foot of snow”? Fair question!

In our milder winters, when snow comes and goes, evergreen groundcovers do offer structure and winter interest in the garden. And they benefit birds and small mammals, providing cover from predators and shelter from icy winds. But not so with ivy or pachysandra! Both are invasive, non-native plants that must be prevented from running into wooded areas where they smother everything! Fortunately, there are native evergreen groundcovers much better suited to our landscapes and helpful, rather than harmful, to the ecosystem.

We recently described Leucothoe, a native evergreen that can replace pachysandra as a ground cover under trees and shrubs and in wooded areas.

Another evergreen woodland plant we love is Christmas fern (Polystichum acrostichoides). Not truly a groundcover, because it stays in place rather than spreading itself around, Christmas fern can be planted densely to fill in a shady area. Deer won’t eat it, and it’s such a pleasure to see a green fern in the dead of winter.

Evergreen Christmas fern brightens the winter landscape

Perhaps the best known native evergreen groundcover in our region is Creeping Juniper (Juniperis horizontalis). Juniper is a versatile shrub that provides significant value for wildlife year-round. Its dense branches provide good hiding places, and its berries feed the birds. It prefers dry soil and full sun, but it tolerates some shade as long as the soil is well-drained. It spreads at a moderate rate, and effectively suppresses weeds. Juniper is also tough — it handles being buried by snowplow build-up, even with road salt! It’s a good choice for curb-side plantings and along sidewalks and driveways.

Creeping Juniper is attractive all winter along a property line

You can see another of our favorite evergreen groundcovers in the foundation planting at the Nature Center’s Manor House. Carex laxiculmis ‘Hobb,’ often sold as ‘Bunny Blue’ sedge, is a great groundcover for shade. It’s maybe more “everblue” than evergreen, so its eye-catching color is striking around and under shrubs, and even under shade trees. It will live happily with dense tree roots and spread itself slowly by short runners that sprout new little plants over time. It holds its blue-green strappy leaves all winter long. You don’t have to cut it back in the spring, but if it looks a bit ragged, you can trim the old leaves before new growth begins. Like most grasses and sedges, it is avoided by deer.

‘Bunny Blue’ sedge in winter under shrubs at the Manor House

Plant ‘Bunny Blue’ sedge with other native shade-lovers for a mix of textures. When the other plants go dormant in the fall, ‘Bunny Blue’ will hold the spot until they return

‘Bunny Blue’ sedge in summer in with Maidenhair Fern and Wild Canadian Ginger

For a sunny area, we like Waldsteinia (or Geum) fragaroides, commonly called “Barren Strawberry” because its leaves look similar to strawberry, but it doesn’t bear fruit. Waldsteinia is a deer-resistant evergreen groundcover that likes sunny dry sites and blooms in early spring with bright yellow flowers. It only gets a few inches tall, so it’s great at the front of a flower bed. We planted it last year at the very front of the Nature Center’s new Pollinator Garden. Be sure to come see it bloom this spring!

Spring growth covers bronzed winter foliage of Waldsteinia

Waldsteinia spreads slowly by shallow runners. Use it around a mailbox or lamp post, or along a sunny path. Snow cover and freezing cold do not bother it, and it is hardy to Zone 4. Its leaves may turn bronze by late winter, but new growth will cover the old in spring and form a weed-suppressing mat. And when April showers bring May flowers, you’ll want to be there.