Forage Turnip and Rapeseed
Fall-seeded Brassicas, turnips and rapeseed, offer weed suppression in the following crop and decompose quickly after being terminated. Turnip and rapeseed grow fast in the fall and are good at reducing surface compaction while providing winter cover and fall weed suppression.
Land Preparation
Smooth, weed-free seedbed, well-drained with enough moisture.
Seeding Rate
Turnips
Forage varieties like Barkant,Twister, Pasja. Purple Top behaves differently. Drill 4-7 lb/ac, 1/2 inch deep. Broadcast 10-12 lb/ac on firm seedbed, cover 1/2 – 3/4 inches. Use the higher rate if fall weed suppression is the goal. Use forage varieties (e.g.Rapeseed and hybrids
Forage varieties like Barsica and Trophy. Dwarf Essex tends to be less vigorous. Drill 5-10 lb/ac, less than 3/4 inches deep. Broadcast 8-14 lb/ac. Cover up to 1 inch. Seed can be no-tilled into suppressed sod or seeded into a conventionally prepared seedbed. Till as necessary to kill the first flush of weeds to ensure a weed free seedbed. After seeding, roll the ground to improve seed-to-soil contact but do not break up soil aggregates.Seed Cost
2024 price: $2.00-$5.00/lb
Seeding Dates
August. See a tool to find the last date for your specific location. (Chose “Mustard.”)
Time Until Control
Frost kill
Seed Suppliers
Ernst Conservation Seed, AMPAC Seed Company. Appin turnip winterkills reliably if sown by August 25. Pasja and Bonar rapeseed may have incomplete winter kill and require control in the spring.
Management Tricks
Roll or drag the ground after planting to ensure good seed-to-soil contact.
Unavoidable Problems
Harbor brassica diseases: do not use in rotations with brassicas.
Avoidable Problems
Slow to establish, prepare a smooth, weed free seed bed. May suppress cucurbit crops that follow.
Classic Uses
Break up compaction, low residue in spring.
Maintenance
Avoid wet spots.
Control
Incorporate in spring, any time before full flowering.
Tips
These cover crops can harbor Brassica disease; do not use in rotation with Brassicas. Useful for suppressing Sclerotinia in lettuce.
Management Goal | Planting Time |
---|---|
Nitrogen Scavenging | Late Summer |
Reduce Surface Hardness | Late Summer |
Reduce Weeds | Late Summer |
Winter Erosion Protection | Late Summer |