For those of you into permaculture, you know the importance of nitrogen fixing plants. These plants, especially when pruned release nitrogen into the soil, helping to boost fertility to the plants nearby. By practicing chop and drop when moisture exceeds evaporation, you can supercharge the establishment of a food forest, or a timber forest. These plants can also be great companions in a garden or orchard. Be careful in the garden, as some nitrogen fixers can be invasive.
Alfalfa
Below is a list of nitrogen fixers to consider establishing in your garden or food forest. (I put a * next to the plants I am personally growing)
|
Common Name |
Plant Type |
Zone Hardiness |
Comments |
|
Black Locust* |
Full Size Tree |
|
Large thorns, some say is allelopathic. |
|
Mimosa* |
Small Tree |
6 |
Edible leaves |
|
Alder* |
Small to Med Tree |
|
Size depends on variety |
|
False Indigo* |
Shrub |
5 |
I had bad luck establishing this plant |
|
Siberian Pea Shrub |
Shrub |
|
|
|
Redbud* |
Small Tree |
5 |
Some debate whether or not it shares the nitrogen it fixes. |
|
Silverberry |
Shrub |
2 |
Eleagnus family |
|
Russian Olive* |
Shrub |
2 |
Said to be invasive, Eleagnus family |
|
Goumi* |
Shrub |
6 |
Good tasting berries, Eleagnus family |
|
Autumn Olive* |
Small Tree |
|
Eleagnus family |
|
Kentucky Coffee Tree* |
Med. Tree |
4 |
I have lots of these trees. |
|
Sea Buckthorn* |
Shrub |
|
|
|
Golden Chain Tree |
Med. Tree |
5 |
Poisonous flowers |
|
Spanish Broom |
Shrub |
8 |
|
|
Afalfa* |
Groundcover |
5 |
Strong tap root |
|
Groundnut |
Groundcover |
|
Edible seed and root |
|
Lupine* |
Groundcover |
5 |
|
|
Sweet Vetch |
Groundcover |
|
|
|
Wisteria |
Vine |
6 |
Very fast growing |
|
Acacia |
Large Tree |
7-10 |
|
|
Mesquite |
Med. Tree |
7 |
Can deal with dry climate |
|
Clover* |
Groundcover |
|
Good for pathways |
Young Food Forest with Swale
References:
Gaia's Garden: A Guide to Home-Scale Permaculture, 2nd Edition by Toby Hemenway
~ Phil Williams
Phil Williams is a permaculture consultant and designer and creator of the website foodproduction101.com. His website provides useful, timely information for the experienced or beginning gardener, landscaper, or permaculturalist. Phil's personal goals are to build soil, restore and regenerate degraded landscapes, grow and raise an abundance of healthy food of great variety, design and install resilient permaculture gardens in the most efficient manner possible, and teach others along the way.
by oliveoilguy 
