Gladius (F1) Brussels Sprout Seed

Scientific name

Brassica oleracea var. gemmifera

Soil and water

Brussels sprouts need fertile soil above pH 6.0 and regular irrigation. Keep them well fed and watered through dry spells so growth never stalls.

Days to maturity

Counted from transplanting. Add about 20 days for direct sowing.

Transplanting

Sow in May, 1/4" deep: 2–3 seeds per cell in 72-cell trays, or 3–4 seeds per inch in open flats. Seedlings are ready to plant out in 4–6 weeks. Set them 18–24" apart in rows 30–36" apart.

Direct sowing

About 4 months before the first expected fall frost, sow 3 seeds at each spot, 18" apart and 1/4–1/2" deep, in rows 30–36" apart; thin each spot to one plant.

Insect pests

Floating row cover from planting day keeps flea beetles and root maggots off young plants; pyrethrin or azadirachtin can be used if flea beetles build up. Bt (Bacillus thuringiensis) controls cabbage worms and loopers. To head off cutworms, work the soil 2–4 weeks before planting to turn in cover crops and weeds.

Disease prevention

Prevention works best: long rotations away from cabbage-family crops, clean seed-starting mix and seedbeds, and strict sanitation of tools and fields.

Topping

For a single harvest of evenly sized sprouts, or to sell whole stalks, pinch out the growing tip (the small rosette of leaves at the top) once the lowest sprouts are 1/2–3/4" across. The whole stalk sizes up in about 4 weeks.

Harvest

Sprouts sweeten after frost. Pick from fall into December in most areas, and through winter where cold is moderate. Choose firm, tight sprouts, snapping off the leaf below each one and then the sprout itself; sprouts higher up keep growing as you work up the stalk.

Storage

Before the ground freezes, pull whole plants, roots and all, and keep them in a humid cooler at 32°F (0°C) or a cold cellar for 4–6 weeks.

Transplants

About 800 plants per 1,000 seeds.

Packet

100 seeds.

Seeds per lb.

About 76,100 on average.