Late Bloomers

In the last weeks of summer, it is a treat to welcome new flowers to the garden that not only bring fresh color, but also nourish our native pollinators before winter arrives. Two species of the perennial plant, Chelone (pronounced “key-LONE-ee”), start blooming in late August and continue well into fall. Both make great additions to gardens in the Eastern US, and both are known by the rather strange common name, “Turtlehead.”

Chelone glabra starts to bloom just before Labor Day

White Turtlehead (Chelone glabra) has a wide native range, extending from Minnesota to Newfoundland and south to Alabama and Georgia (Zones 3 to 9). It is found in marshes, at the edge of wet woodlands, and along the shores of streams and ponds. That native habitat makes White Turtlehead an obvious choice for sunny rain gardens and soggy areas, but it will happily endure hot weather with occasional irrigation. White Turtlehead stands 3 to 4 feet tall and mixes well with Joe Pye Weed and Cardinal Flower.

White Turtlehead in a rain garden

Pink Turtlehead (Chelone lyonii) has a much more limited native range. It evolved in the Appalachian region from Georgia to Virginia, but has become naturalized in New York and parts of New England. Our observations suggest that insects in these northern areas have welcomed Pink Turtlehead, making good use of its nectar, pollen, and leaves. Pink Turtlehead is more tolerant of shade than White Turtlehead, and can be found in moist forest areas in dappled sun.

Chelone lyonii in a protected forest in New York

Pink Turtlehead also grows 3 to 4 feet tall and has an open, somewhat rangy form. There is a widely-available cultivar of Chelone lyonii called ‘Hot Lips’ that is more compact, only 1 to 2 feet tall, with dark green leaves. ‘Hot Lips’ looks great massed under trees or as a front-of-the-border plant in a light-shade garden.

Chelone lyonii ‘Hot Lips’ in late August

Both types of Turtlehead bloom for two months or more, with flowers opening sequentially from the bottom to the top of each stalk.

‘Hot Lips’ in a shade garden in mid-September
‘Hot Lips’ in October

Both the scientific name and the common name relate to the appearance of the flowers as they open. “Chelone” comes from the Greek word for “turtle.” The name makes sense if you see the flower from the side angle – it does look a bit turtle-ish.

 White Turtlehead
Turtle head! (Actually, this is the Nature Center’s Sulcatas tortoise. And as for those turtle “hot lips”? Just recall beauty is in the eye of the beholder.)
Photo: Travis Brady

Chelones are beautiful late bloomers, but the best reason to have these plants in your garden? Entertainment! All day long, wiggling bumblebees work their way into the flowers to find nectar. Bumblebees and carpenter bees are just heavy enough and strong enough to force the flowers open, collect the pollen, and fly off to the next flower. Watch them at work in this video clip:


The nectar pay-off is deep inside the flower, so the bumblebee picks up pollen on the way in and on the way out. The pollen will be transferred to the next flower when the bee brushes against the protruding curved stigma.

What the bee sees…

Turtlehead is a frequent addition to children’s gardens because watching the bumblebees climb into these beautiful blossoms never gets old.


Too Much or Not Enough?

We plant Anise Hyssop (Agastache foeniculum) every chance we get. Any sunny, dry place is perfect.

We planted it in the entry garden at the Greenburgh Nature Center.

Staircase garden

We planted it in the Pollinator Garden.

Gerrie Shapiro Memorial Pollinator Garden

We planted it in the Meadow.

Native Plant Meadow at the Nature Center

We bring it into our butterfly exhibit in containers as a nectar supply.

Monarch and Painted Lady butterflies on Agastache

Whenever we are asked for advice on planting community pollinator gardens, we recommend Anise Hyssop.

Community pollinator garden in Dobbs Ferry, NY
Photo: August Brosnahan
Pollinator garden on the Hudson River

And we always recommend Anise Hyssop for drought-tolerant residential gardens.

Agastache behind Dense Blazing Star and Coneflowers

We just can’t get enough of this excellent plant! Here are the reasons why:

  • It is gorgeous!
  • It blooms from July through September
  • Butterflies and bees love it
  • It is extremely drought-tolerant and does well in poor soil
  • Deer, rabbits, and woodchucks avoid it
  • It is sturdy, upright, and mixes well with other plants
  • It is host to several species of moths and butterflies
  • The leaves are aromatic, edible, and can be used to make herbal tea

Each flower stem of Agastache holds dozens of tiny lavender flowers loaded with nectar. Even when the flowers finally fade, the stalks are attractive and bring around the very last of summer’s bees and butterflies.

 Individual flowers line the stem of Agastache in July
Agastache in mid-September

Anise Hyssop is native to the Great Plains and dry prairies of the American Midwest. Hardy to Zone 4, the only thing it really can’t take is wet soil. It prefers full sun, but can tolerate some shade as long as the soil is very well drained. Plants can disappear over the winter if the ground stays wet for long periods. We replace any that don’t make it with gallon-sized container plants in the spring and they very quickly catch up to the survivors.

Agastache foeniculum grows 3 to 4 feet tall, forms clumps, and doesn’t seem to expand by rhizomes, but it will seed itself around to make new plants in good conditions. There are several cultivars of hybridized plants now widely available in the market. ‘Blue Fortune’ and ‘Black Adder’ both result from a cross between Agastache foeniculum and Agastache rugosa, an Asian plant. Though we prefer the straight species, the hybrids certainly attract bees and butterflies, and have proven themselves durable, at least in Zones 5-7. The hybrids are sterile and will not seed themselves in the garden.

We do have one problem with this plant: deciding how to pronounce the scientific name! Horticulture expert, Bill Cullina, says “ag-OST-ach-ee,” sounding rather like a sneeze. On-line sources, with audio, give the “American” pronunciation as “aga-STASH.” Looking a bit further, however, we find general agreement that the word “Agastache” comes from the Greek words “agan” meaning much or many, and “stachys” meaning ear of grain. Though that description for Agastache foeniculum is a bit puzzling since the flower doesn’t really look like grain to us, the Greek origin of the word does suggest that the appropriate pronunciation is “aga-STACK-ee,” so we go with that. As for “foeniculum,” we pronounce it “fen-ICK-you-lum,” a word that either comes from the Latin “foenum” for hay, or the related Italian word “finocchio” for fennel. The leaves smell much more like fennel than hay!

Unfortunately, the common name, “Anise Hyssop,” doesn’t clear things up. “Anise” makes sense if you smell or taste the leaves, but “Hyssop” is a completely unrelated plant family. In any case, if you’re asking for this wonderful plant, saying either “aga-STACK-ee” or “Anise Hyssop” will work.

So, is this too much of a good thing?

We don’t think so!


About Drought

What makes a plant, or a whole landscape, “drought tolerant”? Why do some plants need water regularly while others are fine without it for weeks or longer? Drought tolerance depends primarily on two factors:

The first is where a plant evolved. Adaptation to particular environments happened over millennia, and most plants will thrive only in conditions very similar to those where they evolved. That is why, when considering a plant for our gardens, we always want to know whether it is native to our region. Plants that evolved in tropical rainforests will never be drought tolerant. On the other hand, plants that evolved in America’s open meadows are well-adapted to life under baking sun with occasional torrential thunderstorms. Those plants can withstand weeks of heat and drought still looking great, and then stand up to the floods that so often follow.

American meadow plants can tolerate weeks of drought and heat without irrigation

The second big factor in drought tolerance is root depth. Plants that evolved in wet climates usually have shallow roots. Plants that evolved in hard-packed prairie have strong, deep roots that force their way down through poor soil to reach and hold any available water. They can withstand long periods of drought. They also can absorb flood water because their roots break up the soil, allowing water to penetrate rather than run off.

Comparative root depth of plants – note lawn grass on the far left.
Graphic used with the permission of artist

As the chart above indicates, many plants that evolved in America’s prairies like Goldenrod, Coneflower, Prairie Dropseed, Switch Grass, and Wild Indigo have very deep roots, reaching down 4 to 8 feet! As a result, they make great garden plants because they are both beautiful and very drought tolerant.

In contrast, lawn grass is not at all drought tolerant. Despite its name, Kentucky Bluegrass is not from Kentucky. It is native to mild climates in Europe and Asia. Lawn grown from typical seed mixes has very shallow roots, about 2 inches deep. Shallow roots do not retain water, so lawn needs frequent irrigation, and in heavy rain, excess water runs off rather than being absorbed and held in the soil.

An unirrigated lawn after 8 weeks of heat and drought
Heavy rainfall rushes off of lawn, dislodging pavers and overwhelming storm drains

But Americans love lawns. Perhaps perfect lawns and tightly-manicured shrubs became a status symbol in America because of our historic connection with England, where 19th Century aristocrats demonstrated their wealth by employing countless servants to hand-cut lawn and trim elaborate hedges.

Landscape fashion among English aristocracy in the 1800’s — Cliveden House, England
Landscape fashion in suburban New York, 2022

Maybe it’s time for a change of fashion? Here is a photo of that same 19th Century landscape this summer:

Cliveden House, England, August 2022 
Photo: Lawrence Siskind

Most of Europe is suffering from heat and drought this summer, and watering restrictions are now in place. Because lawn requires so much water and retains so little, lawn irrigation is usually the first target of water regulation. In the US, lawn watering (not agriculture!) uses an average of 8 billion gallons of water daily – that’s 32 gallons for every man, woman, and child in our country, every day! (Tallamy, Nature’s Best Hope) Clearly, our love for lawns is not sustainable. 

Restrictions on residential landscape watering have been a reality in California and many of our Southwestern states for years now. So, it makes sense that landscape fashion there has rejected big expanses of lawn, and turned instead to drought tolerant native plants.

Front yard in Berkeley, California
Native plant landscape in Tucson, Arizona
Lawn used only as an edger in a Mexican garden

Prolonged periods of drought and low reservoirs are becoming common in the Northeast as well. Watering restrictions were imposed this summer in much of the Hudson River valley. So, it’s time to think about changing landscape fashion here, too. We can reduce our demand for water by replacing at least some of our lawn area with native trees and drought-tolerant shrubs.

Trees, shrubs, and flowering plants replaced lawn here

By planting drought-tolerant native perennials, we can replace even small areas of lawn with color and flowers for pollinators.

A pollinator garden reduces lawn area and is a beautiful addition to this backyard
A raised flower bed full of life is so much more interesting – and drought tolerant – than lawn
 The drought-tolerant staircase garden at the Nature Center would be a stunning entry garden for any residence

Modern American landscapes need to be resilient as well as beautiful. As we rethink landscape fashion, we recognize that there is as much beauty in a vibrant drought-resistant garden as there is in a bare expanse of thirsty lawn. 

For information on drought-tolerant perennials, download the plant list we used for the Nature Center’s pollinator garden here.


Who Was Joe Pye?

Joe Pye Weed is a classic American perennial, and a garden favorite for generations. It is tall, beautiful, long-blooming, and easy to grow. It is a butterfly magnet. Whenever we are asked about the best plants for pollinators, Joe Pye Weed is at the top of the list.

Monarch butterfly on Joe Pye Weed
Painted Lady butterfly on Joe Pye Weed

Native to wet meadows in the Eastern half of the US, Joe Pye Weed nurtures butterflies, bees, and is the host plant for more than three dozen species of moth and butterfly caterpillars. It is a great alternative to non-native “Butterfly bush” (Buddleia spp.), not only because it attracts as many or more butterflies, but because it also allows them to reproduce. Caterpillars native to the US cannot eat the leaves of “Butterfly bush,” so Joe Pye Weed is the right choice if you want more butterflies.

There are five species of Joe Pye Weed, which is the common name of all five plants in the genus Eutrochium (formerly part of the genus Eupatorium), and all are North American natives. The main difference among them for gardeners is height. Hollow Joe Pye (Eupatorium fistulosum) is the tallest at around 10 feet. Spotted Joe Pye (Eupatorium maculatum) is usually about 6 feet tall, and Coastal Joe Pye (Eupatorium dubium) is the shortest at about 4 feet, with a cultivar marketed as ‘Baby Joe’ growing only 3 feet tall. They all bloom from late summer through fall, and they all have big flower clusters in shades of pink to lavender. Hardy in Zones 3 to 9 and deer resistant, Joe Pye looks great at the back of a formal flower bed or along a rustic fence.

Joe Pye in an informal garden

The flowers of Joe Pye Weed go through a fascinating progression. The initial buds are almost silver. From there, they develop into clusters, 4 to 8 inches across, composed of tubular pink blossoms. Each tube then emits a single forked pistil, the female reproductive part. The male pollen-bearing stamens remain hidden inside the tubular structure. The huge array of pistils over the top of the flower mass ultimately creates a fuzzy appearance.

Flower buds in early August
The pistils emerge, indicating available nectar
Large clusters of tubular flowers top each stem
As more flowers open, the cluster begins to look fuzzy

Joe Pye Weed does best in wet sunny areas, so it is perfect for a rain garden, or a low spot too soggy for lawn. Though it is not particularly drought tolerant, Joe Pye manages well in our Meadow at the Nature Center without irrigation.

Joe Pye in a rain garden with White Turtlehead and Swamp Milkweed
Joe Pye Weed in the Meadow at the Nature Center

So, who was Joe Pye and why was this wonderful plant named for him? There was a story, repeated in various forms over the past 100 years or so, that Joe Pye was “an Indian medicine man” who saved an entire colony of English settlers in the 1600’s from typhus fever using a tea made from the plant. As with many such stories, the details often changed in the telling, and the only cited source was “legend has it.” Recently, however, curiosity prompted the first scholarly research on the question, and in 2017, Richard B. Pearce and James S. Pringle published their findings in The Great Lakes Botanist journal. They concluded that the plant was likely named for Joseph Shauquethqueat, a highly-respected Mohican sachem or paramount chief, also known to white neighbors as Joe Pye, who lived in the Mohican community in Stockbridge, Massachusetts in the late 1700’s to early 1800’s. Although there is no evidence that he was an herbalist or ever used or recommended the plant medicinally, many members of the First Nations did know of the medicinal properties of the plant. Pearce and Pringle speculate that since Joseph Shauquethqueat was also a selectman in Stockbridge, well-known and respected by his white neighbors, “it would not have taken many observations of his collecting the plants now called Joe-Pye-weed for medicinal use, or suggestions from him that they use those plants for the treatment of fevers…before someone, when referring to those plants, associated them with the man they knew as Joe Pye.”

Joseph Shauquethqueat was a remarkable man. Remembering him with a plant as remarkable as Joe Pye Weed is a worthy honor, indeed.


Worth a Mint

What makes a garden plant special? Beautiful flowers? Reliability? Long season of bloom? Easy care? Attractive to butterflies? Maybe even useful for humans? Mountain Mint checks all the boxes! This perennial garden plant is so valuable it’s a wonder we don’t see it everywhere.

The only problem with Mountain Mint is its name! The scientific name, Pycnanthemum, is a mouthful, and the common name “Mountain Mint” is just wrong. The plant does not come from the mountains, and it’s not a true mint. It’s actually a plant native to America’s meadows, from New England to the Midwest and from Florida to Texas. And unlike spearmint and peppermint, it is not in the mint genus, Mentha. (Though it does have a decidedly minty flavor, and can be a pretty good alternative.)

We have three species of Mountain Mint at the Nature Center: Pycnanthemum virginiana (“Virginia Mountain Mint”), Pycnanthemum tenufolium (“Narrow-leaved Mountain Mint”) and Pycnanthemum muticum (“Broad-leaved Mountain Mint”). All three grow in our Meadow in full sun, average soil, and without special care or irrigation.

Virginia Mountain Mint
Narrow-leaved Mountain Mint
Broad-leaved Mountain Mint

Our favorite is Broad-leaved Mountain Mint. The plant grows about 3 feet tall with shiny, dark green, and very minty leaves. In early summer, it produces a pair of fuzzy gray-green “bracts,” leaf-like structures that frame a cluster of flower buds at the very top of the plant. The flowers themselves are tiny little polka-dotted tubes that open sequentially over two to three months. The very long sequence of blooms keeps pollinators coming back all summer for fresh nectar.

Tiny flowers keep opening for months

Mountain Mint is incredibly valuable for pollinator gardens. It is loaded with nectar attractive to bees, butterflies, and a wide variety of other pollinating insects. It is very entertaining to count how many different species visit the flowers.

Honey bees love Mountain Mint
Red-banded Hairstreak butterfly
Clubbed Midas Fly is a native pollinator
Native bumblebees do, too!
Golden Digger Wasp sharing flowers with bees
Grey Hairstreak butterfly on Mountain Mint

Apart from its value to pollinators, Mountain Mint is a wonderful garden perennial. It is tough! Deer, rabbits, and woodchucks avoid it. Like most meadow plants, it is drought-tolerant and does best in full sun, though the Broad-leaved species may want more moisture than Narrow-leaved Mountain Mint. Both are hardy in Zones 3 through 9 and both do well in our Meadow without irrigation. The long season of bloom means Mountain Mint looks good well into the fall, and the seed heads add interest if left standing all winter.

September in the Meadow

Mountain Mint has been used by humans for a wide variety of purposes. Indigenous people in the Eastern US made a tea from the leaves to treat headache, stomach problems, and respiratory congestion. Dried leaves of Broad-leaved Mountain Mint are said to make an effective insect repellant when rubbed on skin or clothing. Carrying fresh sprigs in a pocket or under a hat-band helps keep gnats and mosquitos away from gardeners’ faces. The leaves of Broad-leaved Mountain Mint contain pulegone, a substance said to cause liver damage if ingested in significant quantity. But reliable sources assure us that the leaves may be used safely in teas and infusions, and we have some satisfactory experience with that…

A handful of chopped leaves from Broad-leaved Mountain Mint boiled for a few minutes with equal parts sugar and water, then allowed to steep until cool, makes a lovely scented infusion for use flavoring lemonade, iced tea, or even a specialty cocktail! Strain the liquid to remove the leaves and add the syrup to your preferred beverage. Mix a bit of the syrup with gin, lime juice, and elderflower liqueur, and you have a Mountain Mint Martini!