Brussels sprout

By our calculations*, you should look at sowing Brussels sprout about 21 days before your last frost date .

The “small heads”, “buds” or “sprouts” are found at the base of each leaf. These buds are harvested when they attain 1 to 2 inches in diameter, are firm, but before they turn yellow. Harvesting starts about 90 to 100 days after field seeding. The sprouts begin maturing from the bottom upwards. The sprouts can be picked several times or harvest can be delayed and the whole stalk taken at once. In picking, the leaf below the sprout is broken away from the main stem. Harvesting should start before the lower leaves begin turning yellow. Often the central growing point is removed to hasten harvest. This is done when the sprouts are well formed.As the lower leaves and sprouts are removed, the plant continues to grow upwards producing more leaves and sprouts. The plant will withstand frost and can be harvested until freezes occur. The best quality sprouts are produced during periods of sunny days and light frosts at night. Hot weather results in soft, loose or open sprouts of poor quality.

One plant is capable of producing about 2.5 to 3.0. The frequency of harvest and the number of harvests depends entirely on the weather. During the earlier, warm periods harvests may be every 7 to 14 days with about 2 to 6 sprouts being removed per harvest. As the weather becomes cooler harvests may be delayed to once every 3 to 4 weeks, with as many as 10 to 15 sprouts being removed from each plant at each harvest.

Sprouts should be cleaned, trimmed of loose leaves, and sorted to remove those that are soft, damaged, or too large size. Unless refrigerated, the sprouts’ color and quality deteriorate rapidly. They can be stored for periods as long as 30 days if kept at 32 0F and 90 to 95% humidity.¹

Brussels sprouts will cross-pollinate with all other Brassica oleracea, so isolate when going to seed. Dig the plants in fall and pot them in sand. Replant in early spring. Harvest seed pods when dry. ⁵

Black rot, black leg and black leaf spot are seedborne diseases. Hot water treatment can reduce transmission. ⁴

These plants have been known to grow well alongside Brussels sprout so consider planting:

Thyme, Rosemary, Hyssop, Sage and Nepeta : repel cabbage moths
Thyme, Hyssop and Celery: repel white cabbage butterflies
Dill, Garlic, Onions, Celery, Potato and Chamomile: improves flavour
Beetroot: improves soil
Potato: discourage cabbage worms
Nasturtium and Onion: repels aphids

These plants will not grow well with Brussels sprout so avoid planting these within close proximity:

Strawberries: can spread mildews
Tagete minuta: can have herbicide effects
Tomatoes
Grapes
Rue

These problems, diseases and pests are known to affect Brussels sprout plants:

From: ⁴

• Black rot (Xanthomonas campestris pv. campestris) first appears as V-shaped, yellow lesions at leaf margin. Infected plants should be pulled up immediately, and plantings should never be worked during wet conditions.
• Fusarium yellows, caused by the bacteria Fusarium oxysporum f. sp. conglutinan, manifests as yellowing of the lower leaves 2-4 weeks after transplanting. Yellowing moves to upper leaves and ultimately causes wilt.
• Fungal diseases can be prevented by spraying with copper hydroxide (such as Champion WP™and/or oxidate (such as Storox™), but are best prevented by production practices that build soil and promote vigorous plant growth.
• Clubroot is a soil borne disease which stunts the roots of the plants so that they are not able to develop normally. Rotate crops and add lime to raise soil pH to 7.2.

The cabbage aphid, Brevicoryne brassicae, feeds solely on crucifers and can be damaging to broccoli, cabbage, Brussels Sprout, cauliflower, canola, and other plants in the mustard family (Brassicaceae). ²

Insecticidal soap is effective in controlling aphids.

Cabbage looper, imported cabbage worm, and diamondback moth are of the Lepidoptera order and can thus be controlled by Bacillus thuringiensis (such as Dipel DF, see Supplies) and/or spinosad (such as Entrust™), preferentially in rotation with one another to prevent selection of resistant individuals (check with your certifier before applying). ⁴

The modern Brussels sprout that we are familiar with was first cultivated in large quantities in Belgium (hence the name “Brussels” sprouts) as early as 1587. ³

Brussels sprouts

Brassica oleracea var. gemmifera, Brassica oleracea

Misspellings: Brussel Sprout, Brussel sprouts, Brussels sprouts

Our when to plant Brussels sprout estimates are relative to your last frost date. Enter your frost dates and we'll calculate your sowing and planting dates for you!

¹ http://www.ces.ncsu.edu/depts/hort/hil/hil-6.html

² Cranshaw, Whitney. Garden Insects of North America, pp 304-305, Princeton University Press, 2004

³ http://www.brussels-sprouts.com/BSINFO.htm

⁴ High Mowing Seeds – Organic Brussels Sprouts – Growing Information

⁵ http://www.seedsavers.org/instructions.htm