Kentucky Bluegrass Seed Production
Introduction
Kentucky bluegrass is a cool-season, sod-forming perennial grass widely used in the lawn grass industry. It is highly cold-hardy and adapted to a range of soils, performing best on fertile, well-drained soils with pH > 5. Optimal growth occurs in humid areas at temperatures between 15–32°C.
Manitoba’s climate and soils are well suited for Kentucky bluegrass seed production, with yields typically ranging from 300–600 lbs/ac (350–675 kg/ha). Market prices fluctuate with housing and landscaping demand—consult Canadian seed trade members for current pricing.
Plant Development
- Seedlings develop slowly but produce many tillers.
- Tillers must reach sufficient size by fall to respond to short-day, cool-temperature induction for flowering.
- Good seed yields require adequate fall growth and stand thinning to reduce competition among tillers.
Site Selection
- Choose fields free of quackgrass, perennial weeds, and stones.
- Highest yields occur on clay or loam soils; 20 inches (50 cm) annual precipitation is adequate.
- Kentucky bluegrass is apomictic (produces seed without fertilization); isolation for certified seed is only 17 ft (5 m).
Site Preparation
- Summerfallow the year before establishment.
- Apply glyphosate (e.g., Roundup) before tillage to control perennial weeds.
- Prepare a fine, firm seedbed; soil test in fall and fertilize according to recommendations before seeding.
Seeding
- Timing: Spring seeding is best for maximum tiller development before fall induction; late spring to August is possible but reduces seed head formation.
- Depth: ≤¼ inch (6 mm).
- Row Spacing: 12 inches (30 cm) recommended; wider rows for drier conditions.
- Rate: 1–4 lbs/ac (1–4 kg/ha); lower rates for fertile, moist seedbeds and highly tillering cultivars.
- Companion Crops: Avoid if possible; if necessary, use flax at ⅓–½ normal rate.
Harvesting
- Seed ripens by mid-July; harvest when seed heads turn brown.
- Method: Swath and combine; bluegrass does not shatter readily.
- Separation from straw is difficult with conventional combines—may require two passes. Rotary/axial flow combines perform best.
Burning
- Essential for sanitation and stimulating next year’s seed production.
- Burning after harvest can increase seed yield up to six-fold.
- Burn immediately after combining; use a chopper/spreader to prevent hot spots.
Weed Control
- Avenge for wild oat control under companion crops.
- Lontrel for some perennial and annual broadleaf weeds.
- Refer to Manitoba Guide to Crop Protection for current recommendations.
