A Perennial Star
It won’t be long now…the show is about to start!
Each spring, excitement builds as Eastern Bluestar (Amsonia tabernaemontana) breaks ground and gets ready for its performance, which happens in three acts! Amsonia is a 3-season performer. From May through November, this native plant is a star.
The overture starts in mid-spring when shiny green leaves emerge wrapped around deep blue flower buds. The buds ride along as the leafy stalks rise to a height of 30 to 40 inches. Soon, the real show begins as the pale blue stars that give the plant its common name open, attracting a huge variety of pollinators.
The second act lasts all summer long – four full months! Amsonia is a clump-forming perennial that functions almost like a shrub. In time, the plant expands slowly from the base, but does not spread easily either by rhizomes or seed. The glossy foliage looks fresh all summer, reaching about 3 feet tall and almost as wide, and mixes well in a garden border, or even in a meadow planting. The stems may be cut back a bit after flowering to keep the plant’s compact form, or allowed to arch out in a looser shape.
In Act Three, Amsonia turns bright yellow, and the fall color lasts for weeks! It looks great combined with evergreens and fall berries, or mixed with contrasting foliage colors. The plant goes dormant and dies back to the ground in winter after 7 months of extraordinary performance.
Native to moist woodland edges, and along streams and ponds from New York to Florida and west to Texas and Illinois, Eastern Bluestar is happy in Zones 3 through 9. Though its natural habitats are moist areas with well-drained soil, it is quite drought tolerant once it is established, and is reported to tolerate clay as well. It prefers full sun in the northern part of its range, but appreciates some afternoon shade in warmer regions.
Young plants may take a few seasons to get established, but Amsonia is a long-lived perennial. After a few years, the base of the plant becomes quite woody and difficult to divide, but left alone, it comes back year after year for a decade or more. And Amsonia is pest resistant – it has white latex sap that deer and other critters avoid. Gardeners with latex allergies may also wish to avoid it by wearing gloves.
It’s surprising that Eastern Bluestar isn’t better known among today’s gardeners since even its name dates back to Colonial times. Amsonia was named for a physician and amateur botanist, John Amson, who lived in Williamsburg, Virginia and once had a very famous patient. In 1758, George Washington was worried that he had contracted “consumption” (tuberculosis) during the French and Indian War. Fearing the worst, he visited Dr. Amson for advice. The good doctor reassured General Washington that he had nothing more than a common cold and was not going to die. To honor the esteemed Dr. Amson, the botanist John Clayton named the perennial flower “Amsonia” shortly thereafter.
If you go shopping for Amsonia tabernaemontana, you are likely to run into a few other Amsonias, and there can be some confusion here. A variety called Amsonia tabernaemontana var. salicifolia is native to the southeastern U.S. and has slightly narrower leaves than the northern species. It is often sold in nurseries in the Northeast, and is difficult to distinguish unless they are viewed side-by-side. There is no particular reason to avoid salicifolia unless you are in the Northeast and trying to plant strictly local native species.
A more perplexing issue is presented by Amsonia ‘Blue Ice,’ which is being widely sold and is becoming increasingly popular. A few years ago, a commercial grower with a greenhouse full of Amsonia tabernaemontana noticed some plants in the crowd with slightly larger and darker blue flowers and foliage more compact than the species. Horticulturists first classed ‘Blue Ice’ as a “selection,” a naturally-occurring variation with desirable characteristics that is then cultivated for sale by stem cuttings. Further study, however, has suggested that ‘Blue Ice’ is of “uncertain parentage,” which sounds a bit scandalous and could mean that ‘Blue Ice’ is a hybrid or an accidental introduction or something else altogether. At present, although the genetic mystery rules out the plant for purists, it really is a lovely garden perennial. ‘Blue Ice’ stays under 2 feet tall, which is great in smaller gardens.
There is another popular species of Amsonia called Amsonia hubrichtii or Threadleaf Bluestar, which is native only to Arkansas and Oklahoma. Although it is a fine garden plant, and is regularly sold outside its native range, you will maximize ecological benefits in your own area by planting the species that is native there.
For most of the Eastern US, and much of the Southcentral US, Amsonia tabernaemontana, our own Eastern Bluestar, is the true perennial star. Let the show begin!
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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.
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After the Deluge
If you’ve ever enjoyed the sight of rain drops clinging to every leaf of a tree after a storm, you have observed one of the ways trees manage stormwater.
Forests intercept rainwater in the tree canopy, and slow its fall to the forest floor where it is absorbed and filtered before any excess gradually moves to streams. A forest can absorb at least 12 inches of precipitation per hour before surface water begins to move toward natural channels. In urban and suburban areas, with limited tree canopy, heavy rainfall hits the ground immediately and accumulates on impermeable surfaces, causing flooding.
As rainstorms increase in frequency and intensity, flooded roads, neighborhoods, and basements have become critical problems for municipalities and residents. Storm water run-off from impermeable surfaces too often exceeds the capacity of urban and suburban systems. Engineered solutions to flood control are complicated, expensive, and controversial, so urban planners are increasingly considering “green infrastructure” – essentially, managing stormwater by changing how we landscape.
Trees not only remove carbon dioxide from the atmosphere, feed and shelter wildlife, and reduce energy demand for cooling, they are also the most cost-effective way to manage stormwater. Trees and related landscaping can keep excess water off of roadways, and out of your basement.
Trees manage stormwater in several critical ways. If you’ve ever sheltered from rain by moving under a tree, you’ve experienced “interception.” The tree canopy catches rain and holds raindrops on every leaf, twig, stem, and branch until they evaporate after the storm. A mature evergreen can intercept more than 4,000 gallons of rainwater in a year. In a suburban setting, a single deciduous tree intercepts 500 to 760 gallons per year. And a recent experiment demonstrated that even a small flowering tree can intercept 58 gallons of storm water during a ½ inch rain event, or about 67% of the rain that falls on its canopy. Intercepted stormwater never even touches the ground, so it cannot become run-off or cause flooding.
Rainwater that is not intercepted by the canopy and hits the ground is called “throughfall.” Tree roots, which typically spread at least as wide as the tree canopy and are concentrated in the top 18 to 24 inches of soil, break up compacted soil so that more throughfall infiltrates and is absorbed by the ground. Ground water is then taken up by tree roots, transported to the leaves, and used in photosynthesis. That water ultimately is released back into the atmosphere in a process called “evapotranspiration.”
Trees consume or “transpire” an enormous amount of water. A single mature oak tree can transpire more than 40,000 gallons of water per year! Homeowners who take down mature trees may be shocked to realize that all of that water becomes run-off and a source of flooding when the tree is gone.
A tree surrounded by pavement or lawn takes up less water than a tree in the forest or a tree accompanied by other plants. Leaf litter, groundcovers, and understory plants dramatically increase the ability of the soil to absorb stormwater. By increasing organic matter and leaf surface under trees, both the amount of stormwater held, and the amount available to the tree for evapotranspiration, are increased significantly.
By contrast, lawn grass is barely more effective than pavement at reducing stormwater run-off. The roots of turf grass are only about 2 inches deep and do not retain much water. Mowing, removing lawn clippings, and using leaf blowers all have the effect of compacting lawn and reducing organic matter in the soil, further reducing its ability to take up water. Automatic irrigation systems, programmed to top-water lawn every couple of days without regard to rainfall, add to run-off problems.
Worse, in most communities, storm drains do not channel run-off into sewage treatment facilities, but directly into local waterways, so the chemical fertilizers and pesticides typically applied to lawns are transported by stormwater run-off to our waterways. Pesticides, applied to lawn annually at 10 times the rate used by farmers, are a leading source of water pollution, contaminating groundwater, freshwater streams, rivers, and coastal waters. Lawn fertilizer, washed into storm drains, causes algae blooms and excessive weed growth in waterways.
Suburban residents can make their yards into “green infrastructure” by reducing lawn and planting densely with native trees and other plants. Parking lots, road medians, church and school grounds, apartment complexes, and any place with lawn or paved surfaces can be added to green infrastructure by planting native trees and landscape plants wherever possible. The best way to prevent stormwater run-off from flooding your basement, blocking your street, and reaching our rivers is to capture it in your own yard with the beautiful trees and plants native to our area.
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.
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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.”
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.
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.
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.
Both types of Turtlehead bloom for two months or more, with flowers opening sequentially from the bottom to the top of each stalk.
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.
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.
Turtlehead is a frequent addition to children’s gardens because watching the bumblebees climb into these beautiful blossoms never gets old.
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.
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.
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.
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.
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.
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.
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.