Calabreses in London
Brassica oleracea var. italica
Calabrese (broccoli) produces a large central head of tightly-packed green buds, followed by smaller side-shoots after the main head is cut. It’s a cool-season brassica crop. Grow it in full sun with fertile, well-drained soil and keep plants watered during dry spells. Harvest the heads while firm, then leave the stem in the ground to allow side-shoots to develop.
Growing Guide
Step-by-step instructions for growing Calabrese
Planting Calendar
Growing Guide for
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Sow Calabrese directly outdoors for a later harvest, useful for extending the cropping season into autumn.
1 Sow Seeds Directly
Sow seeds directly into prepared soil from 30th March - 29th April. Make drills deep and space seeds apart, thinning later. Cover lightly with soil and water well. For a continuous harvest, sow a new batch every 21 days until midsummer.
2 Thin Seedlings
Thin seedlings to the final spacing of apart once they have two true leaves, around 28th April - 5th May. Remove the weakest plants, leaving the strongest to grow. Water after thinning to help the remaining plants establish.
3 Install Pest Protection
Protect plants from pests as they grow from 5th May - 12th May. Use fine mesh netting to cover the bed, securing it well to keep out butterflies and birds. Add brassica collars to each plant to prevent root fly damage.
4 Feed Plants
Apply a nitrogen-rich fertiliser every 28 days from 5th November to encourage growth. Use a liquid feed or granular fertiliser, watering it in thoroughly. Discontinue feeding when the central head begins to form.
5 Harvest Calabrese
Cut the main head when it's compact and before the flowers open, from 5th November. Harvest side shoots regularly as they develop until 23rd June. Keep the soil moist to reduce the risk of bolting during dry spells.
Companion Plants
Plants that grow well (or poorly) with Calabrese
Why Companion Planting Matters
Companion planting can help deter pests, improve pollination, enhance growth, and maximize garden space. Some plants release chemicals that repel pests or attract beneficial insects, while others can improve soil quality or provide shade for sensitive plants.
Suggested Varieties
Popular varieties of Calabrese to consider
Belstar
A reliable F1 hybrid with good heat tolerance, producing medium-sized blue-green heads and abundant side shoots. It's resistant to bolting and suitable for UK summers.
Green Magic
An early-maturing variety with uniform, dense heads and a sweet flavour. It performs well in cooler conditions and is ideal for succession sowing.
Ironman
A vigorous F1 hybrid known for its large central head and prolific side shoot production. It has good disease resistance and is well-suited to organic growing.
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