Broken Forest

About Amorpha

Laaaaaaaave legumes. Love saying “legume”, love writing “legume”, love leaves of legumes, tell me you don’t love legumes and I will call you a liah! 

Let’s leaf sweet peas and snap peas and beans out of it (for now) and jump straight to three you maybe didn’t know you can grow:

The Amorphas

There are three native Amorpha species to Manitoba and much of North America. These are unusual perennial woody shrubs promising a lot of pollinators, pinnate foliage, and pretty spike blooms. Plus LEGUME.

The Latin amorpha of Greek origin meaning  “without form” or “deformed” which is a rude twist ending on such a beauty word (for the sake of the argument it has to do with the leaves – it’s not like the other leaves in this family). Being a part of the pea family (good family: Fabaceae) means it’s a legume by group, and like the rest of ’em Amorpha species will fix their own nitrogen – meaning they will like less than perfect soil – meaning they will improve the soil especially if foliage is turned under – meaning they will have extraordinary fresh green leaves and darling pretty blooms – but you had me at legume.

The whole group is better known by the collective moniker “false indigo”.

Don’t grow any of these from seed unless you enjoy delayed gratification. They are so slow growing, just buy young plants from the nursery selling your closest ecotype.

What is an Ecotype?

Totally winging it here, but it’s genetically distinct specimen from a certain geographic area or climactic zone. The plant that evolved closest to your location or in the same climate zone will do the best in your garden. Native plants coming in from a nursery afar may actually be separated from your native species by several thousand years of evolution – a process that could have encoded a humid temperate climate on the plant’s genome, and maybe you live in arid continental. This could screw up bloom time because the latitude was more southerly, this could ensure you have a half-thriving tufted hair grass for most of your life. 

Amorpha_nana

Amorpha nana
AKA Fragrant or dwarf false indigo

Considered rare in the wild (would concur, never seen it) its natural habitat is the open sandy or rocky prairie and open hillsides. It’s just a wee guy between 1 and 2 feet tall.

Scoggan’s Flora of Manitoba (1957) says this one is on the dry prairie of southern Manitoba, with its northernmost observation at Oak Point on a “grassy slope”.

I have yet to see if mine will survive or – dare I dream – flourish, but I planted it in a slightly more black stuff-enriched sandy soil. Apparently it doesn’t like things too, too dry. The Navajo have been documented as smoking it for respiratory trouble.

I’m skipping over this shorty for the other two, but you can read more about it here, including a nice photo from Manitoba’s own prairie plants expert Robert G. Mears (Robert and his partner Colleen Zebeluk restored five acres to native prairie plants, and called it the Silver Plains project, check out their very informative site here).

Amorpha canescens 

AKA Leadplant, downy indigo bush, prairie shoestring, buffalo bellows

Amorpha canescens

Amorpha canescens with wood lily amidst big bluestem a decade after the Sandilands forest fire.

Meet a species of dry, sandy prairies associated most predominantly with big bluestem (Andropogon spp.), dropseed (Sporobolous spp.) and grama grass (Bouteloua spp.). There aren’t many shrubs that evolved on the open prairie, but this is one. Wants full sun.

It captured the attention of horticulturalists because of its intricate silvery foliage and large spike blooms in a deep violet (faux indigo?) colour. 

I’ve found it in the wild in Sandilands Provincial Forest after a jack pine forest burned and was reclaimed by tall grass prairie. A single plant can support 30 flowering stems from its woody base and 3000 individual flowers – pollinated by a wide diversity of insects, including solitary bees, honeybees and beetles.

This is a tap-rooted plant so once it’s been given a spot, any attempt to shuffle it around will kill it. Choose wisely. Growwwwwsssss slooooooowwwwwwwwww. 

Scoggan observation: dry prairie of southern Manitoba, northernmost collection at Brokenhead, 30 miles northeast of Winnipeg. 

Amorpha fructicosa

AKA Desert false indigo, false indigo-bush

Amorpha fructicosa

Amorpha fructicosa likes it wetter than where I have it here. Blooms at the same time as the wild rose, june grass, sheep fescue and hardy salvia (among others) in late June.

 

This frothy green shrub can reach 12 feet tall and span 15 feet wide but is smaller in other regions, as short as 4 feet. It’s a North American native that’s escaped from gardens in Europe where it is considered a noxious invasive weed (they gave us Canada thistle so we aren’t even yet, who holds grudges I don’t).

Native habitat is strongly associated with waterways, which folks think plays a role in how it disperses its seeds. Think edges of ponds, streams, gullies, ditches, floodplains and moist open woods. So a bit of shade seems ok when you think of how lush these places will be with overhead foliage here and there. 

As I write this I realize that my own young shrubs are probably not super happy where they are – about 15 feet away from a muddy swamp but not close enough to stick their toes in it. (See this is what happens when you wishful-think your dry woodland for moist. THE RIGHT PLANT IN THE RIGHT PLACE.)

 Scoggan observation: Thickets and shores of southern Manitoba. Northernmost collection at East Selkirk on the border of elm woods. First collection found in Morris, 35 miles south of Winnipeg in thickets by the Red River in 1896.


And now we know a lil’ bit about some beautiful legumes for the landscape. Next time might be about baptisia – omg you will really love baptisia.