Louis Raymond experiments in his own gardens like

a mad scientist, searching out plants that most people have

never seen before & figuring out how to make them perform.- The Boston Globe

…Louis Raymond ensures that trees can grow in Brooklyn…

or just about any other place where concrete consumes

the dirt and skyscrapers shield the sunshine.- USA Today


NEW Trips to Take!

Myrtle's easy when the conditions are right.


NEW Plants to Try!

Louis tries to capture the exact words to describe the fleeting but deep pleasures to be found in these Summer-into-Autumn incredibles.


New Gardening to Do!

Allergic to bees? You can still have an exciting garden, full of flowers and color and wildlife.


Plant Profiles




With its dense clusters of bonnet-like flowers borne by vines with pinnate foliage, this was definitely a member of the Pea family. But (alas!) no wisteria begins flowering in late August. But groundnut does. Native to most of eastern North America, Apios americana produces far-ranging rhizomatous roots with rounded swellings along their lengths. The overall look is of a buried chain of walnuts. These tubers are highly nutritious and tasty, with nearly three times the protein content of potatoes. Groundnut was a staple of indigenous peoples as well as, now and again, European settlers.


Although groundnut can be grown as a food crop, its unusual flowering season suggests use as an ornamental. Although the flower clusters are barely a couple of inches across, the blooms are lushly attractive when you finally notice them. And more than a little peculiar. In the picture below, the pale pink-white arching structure, known as the keel, conceals the stamens and pistil. Instead of revealing even their tips to potential pollinators, the keel curves into the ruby folds of the hood. Only a heavy pollinator (a bee, usually) can disturb a receptively ripe flower enough to—surprise!—cause the keel to spring outward, exposing the stamens and pistil at last. The pollen-laden anthers are "thwacked" against the insect's belly. Please, please, won't someone capture this drama on video—and then YouTube it? What is the reaction of the insect? "What the heck was that?" "Finally, damn it"? "Only another thousand before my shift is up"? Or, "Was it good for you?"




Clusters of flowers emerge at each leaf axil; the flowering season lasts for weeks.  




Before starting into bloom, Apios americana appears to be just another What's It? with pinnate foliage.




Here's how to grow this native vine, and how to highlight its eccentric beauty:


Latin Name

Apios americana

Common Name



Fabaceae, the Pea family.

What kind of plant is it?

Perennial herbaceous twining vine.


Zones 3 - 9


Slender stems twine through and up any available structure, from adjacent shrubs and sturdy perennials, to strings, trellising, or harvested branches that you poke into the soil. Apios is nothing if not opportunistic, and cultivation is usually a matter more of control than of encouragement. 

Rate of Growth

Medium to fast. Colonies can take a year to establish, so be forgiving the first season.

Size in ten years

Stems of mature colonies can twine ten to twelve feet. If conditions are right (see "Culture," below), spread can be substantial. Tubers are formed all along the string-like roots, sometimes at a surprising distance from emerging stems. Harvesting never removes all the tubers, especially the outliers, so gradual expansion of the colony is often unavoidable.


Variable: Some colonies form just as a light "scrim" of growth, while others grow densely enough to shade out and smother anything smaller. 

Grown for

its curiosity: Groundnut's pinnate foliage, small dense clusters of pea-like blooms, and twining habit create a strong but superficial resemblence to another native vine, Wisteria frutescens. The two differ greatly in their details: The Wisteria is a woody vine, whereas Apios is herbaceous. Leaves of the Wisteria have nine to fifteen leaflets, whereas those of Apios often have as few as three and never more than nine. And, of course, the Wisteria flowers appear in Spring, and are larger and generally lavender, whereas the Apios flowers appear in late Summer, are smaller, and are always in shades of cream, pink, and burgundy. Then, in August, months after true wisteria, it begins flowering, and beautifully. Groundnut is one of the continent's major indigenous food crops, without which the survival of Pilgrim colonizers would have been in doubt. Apios is one of the garden's more eccentric "Who knew?" members.



its flowers: Small and tightly grouped in a stubby raceme, they  seem modest at first glance. But not at the second! As a Purdue University source details, "Apios flowers are distinct in having a relatively large concave standard with a small hood at its apex into which the narrow sickle-shaped keel is hooked. The keel contains the style and the diadelphous stamens. The intricate floral structure involves an explosive tripping mechanism that usually requires insect activation." Apios would seem to be a great candidate for high-resolution stop-action photography. It's not often a plant has developed an "explosive tripping mechanism." And what happens to the insect?


The differences in coloring of the blooms' parts reward closer and closer inspection. The outer petal is known as the standard (or banner); in my form of Apios, it has a fleshy pink exterior. (See "Variants," below for forms with other coloring.) The standard encloses a cryptic array of vividly colorful elements whose mysterious interpenetration seems counter to the basic function of flowers: to provide clear direction and invitation to  pollen and nectar seekers. Yes, at first the floral parts of Apios seem inviting. They are dramatically contrasting and intriguing in their various palettes and shapes. But on second look, the flowers' structure is almost blushingly enclosed, with the narrow, rigid, pale keel curving up into the luxuriant folds of the deep burgundy hood. It all seems to be a means of (gulp) hermaphroditic self-pleasuring, not pollinatory outreach. Worse, it's all happening in broad daylight and in public. Here's a series of extraordinarily detailed close-ups of a flower of a wild pea, whose structure is simpler to understand, and whose motives (if any flower could be ascribed as having them) are less blushingly self-involved.


The flowers' fragrance is usually described as similar to that of lilacs or violets. 



its edibility: From tubers to young shoots to flowers to the seeds in its pods, Apios is nutritious and even tasty. But this vine is unlikely ever to go mainstream as a food crop. See "Quirks," below for a fuller look at its agricultural challenges, as well as a link to a clear-eyed but also affectionate Apios overview. 

Flowering season

Late in Summer: August into September. Apios is worth cultivating for its curious late-season flowers alone. 

Color combinations

Although there is variance in the coloring of the flowers, the differences are all on one side or another of pink. The green foliage goes with everything, and the vine doesn't create other seasonal displays that might overrule the pink-centric flowers. Combine with white, pink, rose, burgundy, blue, or gray.

Plant partners

I discovered Apios in my own garden as a volunteer twining through shrubbery. This seems to be more than the stems' need to wrap around and through anything that's (literally) within reach. Time and again, sources say that the vine associates itself closely with plants that can serve as scaffolding, and not just above-ground: Even the vine's roots seem to intergrow with those of its host. The relationship is not parasitic and, as long as the host is sturdy enough to support the Apios stems, and large enough that the majority of its foliage canopy is higher than those stems can twine, there seems to be no detriment.  


Partner plants, then, would need to be eight to ten feet tall and sturdy. Because Apios is herbaceous, with all of that season's growth beginning each season as new stems emerging from the roots, even a large and fast-growing perennial, annual, or ornamental grass could host this vine with stability as well as style. Apios could scramble through the lower reaches, say, of one of the larger forms of Miscanthus, providing a leafy and flowering dress-up for these grasses' bare ankles and knees. Or set it loose on 'Jonesboro Giant' vernonia, whose stems soar twelve feet. If you don't mind putting up a few verticals of twine each Spring, let Apios clothe the trunk of a pollarded AcerCatalpa, Liriodendron, LiquidambarPlatanusor Salix. Or let it cover the awkwardly stubby base and lower portions of a Cotinus or Physocarpus that you (correctly) cut down to a foot or two each year.


Some of these woody hosts also have forms whose foliage is colorful through the Summer and, so, can strike up an intricate August and September harmony with the pink, rose, and burgundy details of the Apios flowers. Where possible, the links above are to such forms.


My first choice for a living scaffold for Apios will be my pair of Pinus koraiensis 'Silveray'. This conifer's densely-arrayed, swirling blue and green needles will be a lively contrast to the wisteria-like green leaves of Apios. And if I'm lucky, the vine's higher clusters of rosy-pink flowers will form near some of the conifer's large cones, which emerge blue-green.  

Where to use it in your garden

Apios is probably most often found as a volunteer and, if your gardening tends toward the fastidious, an unwanted one. The colony in my garden—which I can only assume has been in place for many years, twining up through a huge and, therefore, very old boxwood—was not prominent enough to draw the closer attention the flowers need. At least for me, growth is a filigree of foliage and flowers, not an enveloping curtain, and so I'll introduce Apios as a companion climber to equally-large host shrubs in my pink borders. See plenty of possible "Plant partners," above.


Apios can also grow more vigorously, so much so that it needs sequestering almost as you would a bamboo, with its roots contained by surrounding masonry walls or expanses of concrete or asphalt pavement. If these are your circumstances, groundnut might be intriguing as well as attractive as it provides warm-weather coverage up vertical strings or wires placed an inch or two out from a masonry wall. If a walkway is what contains the colony at the front, all the better: The flowers are modestly fragrant and are so detailed in coloring, and eccentric in their spiraling structure, that they are a pleasure to experience at close quarters.


In the wild, Apios is commonly found growing along fresh water, where the ground can be expected to be saturated much of the time. The plant will also thrive in ground that has only normal levels of moisture. As would be no surprise given its stream- and pond-side preference, Apios is not particularly drought-tolerant. Plants tolerate shade, but are more vigorous in sun. 

How to handle it: The Basics

Plant any time tubers become available. Because they are, after all, tubers—storage structures—initial watering would be needed only if prolonged hot and dry weather is the norm at the time of planting. Apios is a nitrogen-fixing species; the fixation is the result of symbiosis between the plant and a partnering bacterium. In general, the greater amount of nitrogen fixed, the greater the vigor of the plant (and, for those growing Apios as an edible crop, the larger the production of pods and tubers.) Although sources don't routinely recommend this, there would be no downside to innoculating the tubers at the time of planting with a commercially-available form of a compatible bacterium. Cowpea innoculant has been sited as the one to use. 


If you are growing Apios as an ornamental, where only modest growth is fine or even desirable, innoculation is probably not necessary.  

How to handle it: Another option—or two? 

Growing Apios as a food crop is beyond my scope of expertise and (candidly) interest. See the daunting practical challenges in "Quirks and special cases," below. If you still can't resist, here's detailed advice from a veritable groundnut geek on Apios cultivation as a food crop.

Quirks and special cases

Ah, the seeming potential, and maddening practical challenges, of Apios as a mainstream food crop. On the one hand, the vines' roots fix their own nitrogen, which would be a great advantage over other root crops such as potatoes and yams, which need expensive nitrogen-rich fertilizer. Apios doesn't need fertilizer at all. But on the other, hand, the largest tubers are formed when plants are allowed more than one growing season, so groundnut is less like a quick crop such as corn or potatoes, and more like a long-term commitment such as grapes and berries, or fruit and nut trees. Further, vining plants, in general, are much more labor intensive than non-vining ones, and this difference is only magnified when they are grown as large-scale crops. Then, there's that companion-plant thing: How could acre after acre of Apios be grown if what its roots prefer is to grow amid the roots of other species? The potential for mechanized harvesting would seem to be zero. At the minimum, development of non-vining cultivars would be necessary if Apios is ever to find a place in our diet beyond that of a once-every-few-years oddity.


The number of leaflets is reported to increase with the age of the plant. Leaves of first-year plant may have a few as three to five, whereas leaves of oldsters may have as many as nine. Given that the the size of the tuber increases with plant age, this is at least a possible help in selecting older plants from the colony. But Apios twines and scrambles opportunistically and, because any tuber that becomes separated from the mother plant (as would happen routinely during harvesting) can sprout to form a new plant, Apios usually grows in impenetrable multi-generational tangles. You would need to be patient indeed to follow the stems that produce conspicuously larger leaves down through the skein of growth all the way to the ground—and then dig up just those larger tubers. Rather, tuber harvesting is similar to panning for gold: You select a promising spot, and are grateful for whatever you can harvest, big or small.


Here is a thorough, thoughtful, and even touching overview of the possibilities as well as limitations of Apios as a larger-scale food crop. Plus, a recipe or two on how to cook it.


The roots of Apios can spread enthusiastically, with new shoots emerging at surprising distance. Be prepared to yank unwanted shoots or dig up the far-flung chains of tuberous rhizomes.     


Although the flowers of a given vine are all of consistent coloring, there are forms whose flowers are lighter as well as darker than mine. I've seen a picture of a form with flowers that are solid burgundy outside and inside; ah, to be gifted a tuber! To my knowledge, Apios is commercially available only by tuber intended for cultivation as a food crop, not as an ornamental; there don't seem to be any named forms that are generally available, nor forms sold by flower color. There are many forms derived from crosses among native-collected plants as part of research at Louisiana State University to develop domesticated higher-yield forms, but they don't seem to be on the market. This research is reported as continuing at Iowa State University.


Flowers of Apios priceana range from greenish white to brownish pink; this species is native from Illinois to Mississippi.


Apios fortunei is native to China and Japan; in Japan it and Apios americana are actively cultivated as food crops. Its flowers appear in a range of colors and combinations of greenish white or yellow with pink or rose.


On-line and, possibly, already right in your neighborhood. 


By tuber. The seeds are reported to have a poor rate of germination.

Native habitat

Apios americana is broadly native to eastern and central North America, from Quebec to Florida and as far west as eastern Colorado.

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