Buckwheat
Note: A longer Buckwheat Cover Crop Handbook for the Northeast is also available. Additionally, please see “The life of a buckwheat plant”. Buckwheat is a short season annual with a delicate, fibrous root system. Since it establishes quickly, it is useful for weed suppression. It also mellows the soil while improving aggregate stability. Classic uses include: ground cover after early vegetables, cover before planting strawberry beds, and bringing idle land into production. Buckwheat does well in low-fertility soils. It is a scavenger of phosphorus and calcium and mineralizes rock phosphate, making these nutrients available for later crops. Residue from the succulent buckwheat plants decomposes quickly. Buckwheat uses the shortest window of opportunity of any cover crop.
Land Preparation
A well-prepared seedbed is necessary to ensure a quick start for the crop. Avoid wet spots; buckwheat will not recover from flooding. Use minimal fertilizer. On established vegetable ground, residual nutrients are sufficient.
Seeding Rate
50 lb/ac drilled, 1/2 to 1 in. depth. 70 lb/ac broadcast
Seed Cost
2024 price: $0.80 to $1.10/lb
Seeding Dates
June-July for complete weed control. Although will grow if planted as early as May 20 or as late as August 15, it will provide less weed suppression at those ends of the planting window.
Time Until Control
35-40 days, 10 days after onset of flowering.
Seed Suppliers
Seedway, Albert Lea, Lakeshore Organic Grain, Kings Agriseed, Ernst Conservation Seed.
Management Tricks
Don't plant into hard soil. Avoid wet spots. Control on time.
Unavoidable Problems
Flooding stops seedling growth permanently.
Avoidable Problems
Gaps: plant evenly on a well prepared seedbed. Weak growth: avoid hard soil, wet spots. Don't plant just before a heavy rainstorm. Volunteers: Kill before seeds fill, usually 35-40 days from summer planting. (Timely termination is not possible in cover-crop mixtures, so buckwheat will become a weed in crops that follow buckwheat-containing cover-crop mixtures.)
Classic Uses
- After early harvested vegetables
- Before and after sequential plantings of vegetables
- bringing idle ground into production
- before strawberries
- A grain crop on low-fertility soils
Maintenance
No pesticides are needed; a good crop for organic rotations. Heavy rain reduces emergence; reseed if necessary. A well-established buckwheat canopy completely covers the ground. Plants often wilt during hot days but quickly recover.
Control
Mow 35-40 days after seeding or incorporate 35-45 days after seeding to avoid volunteers. The right time is when the field has just turned white with flowers.
Tips
Do not plant into hard soil. Buckwheat will not break up hard pan. Flooding stops growth permanently. Weeds will grow in any gaps over 10 inches. Parasitic wasps, ladybugs, and hoverflies are beneficial insects that are attracted to buckwheat. Harmful insects, such as tarnished plant bugs and aphids, are also attracted. However, aphids can serve as a food source for the beneficials. Buckwheat is discussed in the article on Mid and late summer cover crops.
| Management Goal | Planting Time |
|---|---|
| Nitrogen Scavenging | Early Summer |
| Reduce Weeds | Early Summer |
| Stabilize Soil Aggregates | Early Summer |
| Stabilize Soil Aggregates | Summer |
| Reduce Weeds | Summer |