Gardening Articles: Landscaping :: Yard & Garden Planning

Fall Garden Cover Crops (page 4 of 4)

by Charlie Nardozzi

Four Kinds of Cover Crops

Hardy legumes increase soil nitrogen and organic matter. After a slow fall start, they grow rapidly in March and April and may not mature until May in some regions. Mow these cover crops in spring at or before flowering, then till them under.

Field pea (Pisum arvense and P. sativus). Grows 6 inches to 5 feet high; hardy to 10 to 20° F. 'Austrian Winter' pea is low growing, late maturing. 'Magnus' grows to 5 feet. Sow 2 to 4 pounds per 1,000 square feet.

Berseem clover (Trifolium alexandrinum). Grows 1 to 2 feet high; hardy to 20° F. Will regrow after cutting. Produces high amounts of nitrogen. Sow 2 pounds per 1,000 square feet.

Crimson clover (T. incarnatum). Grows 18 inches high; hardy to 10° F. Matures late and fixes less nitrogen than other clovers. Attracts bees. Sow 1/2 to 2 pounds per 1,000 square feet.

Dutch white clover (T. repens). Grows 6 to 8 inches high; hardy to -20° F. Perennial and shade tolerant so may become weedy. Sow 1/2 to 1 pounds per 1,000 square feet.

Hairy vetch (Vicia villosa). Grows to 2 feet high; hardy to -15° F. Hardiest annual legume. Tolerates poor soil, matures late. Sow 1 to 2 pounds per 1,000 square feet.

Fava beans (V. faba). Grows 3 to 8 feet high; hardy to 15° F. Bell bean is a shorter (3 foot) relative. Sow 2 to 5 pounds per 1,000 square feet.

Tropical legumes grow quickly in fall to increase soil nitrogen and add abundant organic matter, but need warm growing conditions. Plant in late summer or early fall in the Southeast and Southwest before winter cover crops. Best grown as summer annuals in the North.

Sunn hemp (Crotolaria juncea). Grows 5 to 6 feet high; hardy to 28° F. Needs same growing conditions as corn. Cut or mow before stems become woody. Can also reduce nematodes. Sow 1 to 2 pounds per 1,000 square feet.

Sesbania (S. macrocarpa). Grows 6 to 8 feet high; hardy to 32° F. Grow like sunn hemp, but more tolerant of flooding, drought, salinity, low fertility. Sow 1 pound per 1,000 square feet.

Cowpea (Vigna sinensis). Grows 1 to 2 feet high; hardy to 32° F. Tolerates poor and acidic soils. Prefers humidity and tolerates drought. Sow 2 to 3 pounds per 1,000 square feet.

Grasses grow quickly, tolerate cold, increase organic matter, and improve compacted soils' structure. They also control erosion but don't increase nitrogen. Mow these annual grass cover crops in spring before seeds set, or till under.

Oats (Avena sativa). Grows 2 to 3 feet tall; hardy to 10 to 20° F. Produces least organic matter of grasses, but tolerant of wet soils. Sow 2 pounds per 1,000 square feet.

Barley (Hordeum vulgare). Grows 2 to 3 feet tall; hardy 0 to 10° F. Fast maturing and tolerant of dry and saline soils; intolerant of acidic soil. Sow 2 to 3 pounds per 1,000 square feet.

Annual ryegrass (Lolium multiflorum). Grows 2 to 3 feet high; hardy to -20° F. Fast growing and tolerates flooding. Absorbs excess nitrogen from soil. Can become weedy. Sow 1/2 to 2 pounds per 1,000 square feet.

Winter rye (Secale cereale). Grows 4 to 5 feet tall; hardy to -30° F. Best grass for cold winter climates; tolerant of low fertility, acidic soils. Sow 2 to 3 pounds per 1,000 square feet.

Other annual cover crops such as buckwheat, mustard, and phacelia aren't ordinarily considered fall crops. They increase organic matter but not nitrogen.

Buckwheat (Fagopyrum esculentum). Grows 1 to 3 feet tall; hardy to 32° F. Fast growing warm season crop. Grow in summer in North, Fall in South. Sow 3 pounds per 1,000 square feet.

Brown or black mustard (Brassica species). Grows 1 to 3 feet high; hardy to 0° F. Strong taproot mines minerals, but can become a pest. Attracts bees. Sow 1 pound per 1,000 square feet.

Phacelia (P. tanacetifolia). Grows 2 to 3 feet tall; hardy to 20° F. Fast-growing succulent plant. Absorbs excess nitrogen and calcium in soils. Attracts bees. Sow 1/4 pound per 1,000 square feet.

Oilseed radish (Raphanus sativus). Grows 2 to 3 feet tall; hardy to 20° F. Grows fast with a strong taproot. Kills nematodes when tilled into soil, but may harbor Brassica family diseases. Sow 2 pounds per 1,000 square feet.

Photography by National Gardening.com

Viewing page 4 of 4
Donate Today

The Garden in Every School Initiative

Special Report - Garden to Table

— ADVERTISEMENTS —