Cover every bare patch of a food forest with a low, edible or soil-building ground cover such as strawberry or white clover, and add perennial root crops such as Jerusalem artichoke and groundnut that grow underground beneath the plants above. Ground cover shades out weeds and protects the soil surface, but it also competes for water and for nutrients with young trees, so keep a mulched circle around each new trunk. Root crops give buried calories, but Jerusalem artichoke spreads aggressively and is hard to remove once planted.
Ground cover is the low layer that protects the soil surface, and root crops are the perennial staples harvested from below it, such as Jerusalem artichoke and groundnut.
Bare Soil Is An Invitation To Weeds, So Cover It With Something Useful
In a woodland the soil is almost never bare. In a young food forest it is: the trees are small and the space between them is open. The carrier recommends heavy mulch in the early years and seeding ground covers between trees, then relying on the ground covers to dominate and hold weeds down once the system matures.
The carrier lists, for the ground layer, strawberry, wintergreen, creeping thyme and nasturtium as edible, and white clover and creeping comfrey as functional; for the root layer, Jerusalem artichoke (sunchoke), groundnut (Apios americana), Chinese artichoke, comfrey roots and horseradish.
Ground Cover Competes With Young Trees
A thick sward right up to a young trunk takes water and nutrients from a tree that has few roots yet. The mulched circle that the carrier advises for the early years is the answer: bare or mulched ground close to the tree, ground cover further out. As the tree grows, move the edge of the circle outwards. See Mulching for the mulch itself and Cover Crops for covers used on open ground.
Method: Establish A Cover And A Root Layer
Step 1: Sheet-mulch first. Lay cardboard or other weed barrier covered with wood chips or leaves before planting. The carrier suggests 6-12 inches of chips or leaves over cardboard. Cut holes for plants.
Step 2: Plant the cover in patches, spacing strawberry runners or clover seed according to how fast you need the soil covered. Slower covers need more weeding early on.
Step 3: Plant root crops where you can dig. Tubers are harvested by digging, which disturbs the roots of neighbours. Keep them in beds or in clear strips between tree rows rather than at the base of a young tree.
Step 4: Contain spreaders. Jerusalem artichoke regrows from any tuber left in the soil. Plant it in an edge strip, or where it can be mown or grazed around.
Step 5: Harvest roots in the dormant season and leave some tubers behind for regrowth, or replant selected ones.
Common Mistakes
- Planting an aggressive root crop in the middle of the planting — it takes over and cannot be removed without disturbing everything near it.
- Letting grass form the ground cover — grass is a strong competitor of young fruit trees; keep it away from trunks.
- Digging under mature trees — repeated digging damages shallow feeder roots.
Safety
Identify wild-collected stock before you eat the roots
Do not eat any tuber you have not identified with certainty. Several wild plants that grow in damp ground look like edible tubers and are poisonous. Plant only stock whose identity you have confirmed, and label root beds.
What’s Next
- Learn next: Vine and Climber Integration — the layer that climbs the others
- Combine with: Nitrogen-Fixing Companions — clover and other covers that feed the soil