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Cornell University

Cover Crop Guide for NY Growers

Dr. Thomas Björkman, Horticulture Section, Cornell AgriTech


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, $15-25/ac.

Seed Cost

2007 price: $0.38/lb

Seeding Dates

June-July. It can be planted as early as May 20 or as late as August 15 but will give less growth.

Time Until Control

40 days, 10 days after onset of flowering.

Seed Suppliers

Birkett Mills, Lakeshore Organic Grain, Agriculver, Ernst Conservation Seed.

Management Tricks

Don't plant into hard soil. Avoid wet spots. Control on time.

Unavoidable Problems

Flooding stops 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, 50 d from late spring planting.

Classic Uses

After early harvested vegetables, bringing idle ground into production, before strawberries. Crop on low fertility soils.


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.


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.


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.

All uses for Buckwheat
Management Goal Planting Time
Attract Beneficial Insects Early Summer
Nitrogen Scavenging Early Summer
Reduce Weeds Early Summer
Stabilize Soil Aggregates Early Summer
Attract Beneficial Insects Summer
Stabilize Soil Aggregates Summer
Reduce Weeds Summer