FoodProduction101

Nitrogen Fixing Trees, Shrubs, and Ground Covers

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: (I put a * next to the plants I am personally growing)

 

Plant Type

Common Name

Zone Hardiness

Comments

Full Size Tree

Black Locust*

3

Large thorns, some say is allelopathic.

Small Tree

Mimosa*

6

Edible leaves

Small to Med Tree

Alder*

3

Size depends on variety

Shrub

False Indigo*

5

I had bad luck establishing this plant

Shrub

Siberian Pea Shrub

3

 

Small Tree

Redbud*

5

Some debate whether or not it shares the nitrogen it fixes.

Shrub

Silverberry

2

Eleagnus family

Shrub

Russian Olive*

2

Said to be invasive, Eleagnus family

Shrub

Goumi*

6

Good tasting berries, Eleagnus family

Small Tree

Autumn Olive*

3

Eleagnus family

Med. Tree

Kentucky Coffee Tree*

4

I have lots of these trees.

Shrub

Sea Buckthorn*

3

 

Med. Tree

Golden Chain Tree

5

Poisonous flowers

Shrub

Spanish Broom

8

 

Groundcover

Afalfa*

5

Strong tap root

Groundcover

Groundnut

3

Edible seed and root

Groundcover

Lupine*

5

 

Groundcover

Sweet Vetch

3

 

Vine

Wisteria

6

Very fast growing

Large Tree

Acacia

7-10

 

Med. Tree

Mesquite

7

Can deal with dry climate

Groundcover

Clover*

3

Good for pathways

Young Food Forest with Swale

Reference: Toby Hemenway, Gaia’s Garden 

Be Sociable, Share!

Comments

Tell us what you're thinking...
and oh, if you want a pic to show with your comment, go get a gravatar!