shade tolerant nitrogen fixer?

Anyone have any recommendations for shade tolerant (partial and/or full shade) nitrogen fixers?

For what climate?

Scarlet runner bean has a large seed and can thus stretch through the shade and make it to the canopy where it can thrive. I have planted it near rows of trees trees that where over 15 feet tall and had a good crop, mind you the trees where in rows about 25 to 30 feet apart. The best way to plant them is not at the trunk of the tree but near a low branch or my personal favourite, Near (2 feet from) a peach or apple tree as they are smaller. Some pea type, like Vicia cracca can also climb trees but needs some direct light too. In general most legumes do not do well in the shade. My advice would be to grow the legumes in the sun and have lots of critters and fungus in the soil to move your NH3/NH4 around. Big critters move lots of nutrients over a large area (poop sound here).

Sorry, I forgot to mention what type of climate and I guess that makes a huge difference for recommendations. I just wasn't thinking. I am in a Zone 7/8 temperate coastal rainforest.

I am not really familiar with this climate, but you might find some leads in this document from Eric Toensmeier called All Nitrogen Fixers Are Not Created Equal.

I have yet to work with this plant, but licorice might be a good option. I've been reading about it and will be planting out 4 of them in an upcoming landscaping job. One thing to note, though you may have resident mycorrhizae in your soil, you may not have the respective bacteria that associate with fixers. most nitrogen fixers require the symbiosis of these critters. I have not yet found which ones work with licorice but I have half a dozen blends for leguminous species that will drench the roots at planting.

I like fava beans for semi-shady areas in my veggie garden and main orchard/fruit forest. They fix a lot of nitrogen, attract bees (especially bumble bees), tolerate quite a bit of shade, survive most winters, self-seed themselves and provide delicious protein that can easily be frozen or dried. It's my main companion plant for fruit trees guilds. Red clover and vetch are good for shady spots, too. Some people like Siberian pea shrub, but I'm not sure how well it grows in the shade.

M.K. Dorje Jr. wrote:I like fava beans for semi-shady areas in my veggie garden and main orchard/fruit forest. They fix a lot of nitrogen, attract bees (especially bumble bees), tolerate quite a bit of shade, survive most winters, self-seed themselves and provide delicious protein that can easily be frozen or dried. It's my main companion plant for fruit trees guilds. Red clover and vetch are good for shady spots, too. Some people like Siberian pea shrub, but I'm not sure how well it grows in the shade.

Funny I have planted vetches in the shade before and they sometimes grow a bit but they never reseeded or produced an economically viable crop. I spread the seed on numerous occasions on all parts of the farm but it only naturalizes in the sunnier spots. I think Hawthorns are actinorhizal (n fixers) so I guess I'm lucky cause they compose about 30% of the canopy on the home farm.

M.K. Dorje Jr. wrote:....Some people like Siberian pea shrub, but I'm not sure how well it grows in the shade.

Thanks I didn't think to ever use fava beans as an understory to trees!

From my experience with siberian pea is that is doesn't handle the shade well. With appropriate bacterial and fungal inoculations I have been able to get some to survive but they are spindly and unlikely to provide surplus nitrogen to neighbors.

Vetch came to mind for me as well - specifically Wood Vetch (I seem to recall reading about it in Edible Forest Gardens - so try there to find out more details). As I remember, it is said to be tolerant of shade. I planted some with my blueberries last fall, and was surprised just the other day to see it going wild with extensive vegetative growth, clinging to the deer protection cage I have around the young blueberries.

This page looks like a good bet to learn more about vetches - http://tcpermaculture.com/site/2013/06/07/permaculture-plants-vetch/

I would agree that most vetches I've observed were in full sun, but some, like the Wood Vetch, seem fine with partial shade. I doubt they would handle full shade.

What about Hog Peanut? That's worth checking in Edible Forest Gardens too, if you have it. If not, see if you can get it from a library (at the very least!), it's excellent for getting answers to questions like this. You just scan down the nitrogen-fixer column of the plant list in the appendices, and see which ones have shade tolerance. Good luck.

Dutch white clover would work in partial shade...it won't be super happy in full shade...

I second the dutch white clover.
I have them on the east side of the house so they get heavy afternoon shade from the house.
They also get partial shade from large 30ft maple tree nearby. The out compete the grass in this area of the yard

Kalin Brown wrote:Anyone have any recommendations for shade tolerant (partial and/or full shade) nitrogen fixers?

Looks like Buckwheat will take light shade...nitrogen fixing, quick growing and easy to turn under. It is an annual though, it you don't want it setting seed you have to knock it down 10 days after it starts to flower.

I have never heard of buckwheat fixing nitrogen, can you provide a source that states that it does and how much lbs per acre.
EDITED: It is not in the legume family at the very least. http://en.wikipedia.org/wiki/Buckwheat

S Bengi wrote:It is in the legume family at the very least. http://en.wikipedia.org/wiki/Buckwheat

hmm? Family: Polygonaceae

From my still rudimentary knowledge of botany, the legume family is Fabaceae. Buckwheat is in the same family as rhubarb and sorrel.

I have heard other people say that it fixes nitrogen, but I have never seen sources for this and I always thought is was sort of a myth.

S Bengi wrote:I have never heard of buckwheat fixing nitrogen, can you provide a source that states that it does and how much lbs per acre.
It is in the legume family at the very least. http://en.wikipedia.org/wiki/Buckwheat

Not sure where I got the idea of it being nitrogen fixing??? I don't seem to be able to confirm this, it is calcium fixing according to West Coast seeds.
Buckwheat fixes calcium in the soil, and makes an exceptionally good green manure plant. Buckwheat absorbs nutrients that are not available to other plants, and can then be composted or tilled under, releasing those nutrients in accessible forms. Flowers are attractive to pollinators as well as beneficial predatory insects: hover flies, pirate bugs, tachinid flies, and lady beetles.

Clover attracts many beneficials and builds the soil. Helps fight cabbage worms, and increases the number of predatory ground beetles.
Buckwheat info

Myrica pensylvanica, bayberry, is a nitrogen fixing perrenial shrub that tolerates partial shade reasonably well.

Bayberry also produces crops of wax in the berries significant enough that pioneers used them for making candles. I've got one planted, and it's faced bunnies and lived (barely) - but others I've talked to say that in good conditions it grows fast and moves quickly (like many nitrogen-fixers). The shade might make it move more slowly (I've got mine in partial shade), and also might mean lesser crops of the waxy (non-edible) berries. Also, the leaves can be substituted for bay leaves in recipes, which I think is awesome.

Rob Read wrote:Bayberry also produces crops of wax in the berries significant enough that pioneers used them for making candles. I've got one planted, and it's faced bunnies and lived (barely) - but others I've talked to say that in good conditions it grows fast and moves quickly (like many nitrogen-fixers). The shade might make it move more slowly (I've got mine in partial shade), and also might mean lesser crops of the waxy (non-edible) berries. Also, the leaves can be substituted for bay leaves in recipes, which I think is awesome.

Yep, I've heard at least one food writer say they prefer the leaves to bay laurel.
Where I live bayberry grows naturally along rocky seashore and field edges, usually well draining, often under or near spruce trees and juniper. It does well in very poor soil, and tolerates salt and wind. It's also not eaten by deer. That makes it a pioneer species of a sort- it is often one of the first shrubs to spread into abandoned fields after grazing or mowing stops.

Another option would be sea buckthorn (hippophae), or autumn olive, both from the Elaeagnaceae family, both providing fruit and nitrogen fixing.

Elaeagnaceae, the oleaster family, is a plant family of the order Rosales comprising small trees and shrubs, native to temperate regions of the Northern Hemisphere, south into tropical Asia and Australia. The family has 45-50 species in three genera.

They are commonly thorny, with simple leaves often coated with tiny scales or hairs. Most of the species are xerophytes (found in dry habitats); several are also halophytes, tolerating high levels of soil salinity.

The Elaeagnaceae often harbor nitrogen-fixing actinomycetes of the genus Frankia in their roots, making them useful for soil reclamation.[2] This characteristic, together with their production of plentiful seeds, often results in Eleagnaceae being viewed as weeds.

I've been using all three to start a few nitrogen fixing hedgerow windbreaks, along with Siberian pea shrub, american plum, Nanking cherry, hops, and wisteria (also nitrogen fixing).

Yes, actually, I can confirm that Autumn Olive (Elaeagnus umbellata) does quite well in shade, much better than I expected based on most descriptions. I've seen it bearing heavy loads of fruit along wide paths covered with forest on both sides. They are getting a fair amount of light from being at the edge, but quite a bit of shade at their backs as well. I don't think it's known how much nitrogen you 'rob' when harvesting the berries, but likely less than you would if harvesting a legume like Siberian Pea Shrub.

The berries are so good too. Just ate some goumi for the first time yesterday, another Elaeagnus, and they are like big fat (delicious) autumn olives, born more like cherries on the shrub.