Crop type: Calabrese
Brassica oleracea (Italica Group) ‘Green Magic’
Common name: Calabrese ‘Green Magic’
Crop slug: calabrese
This Allotment Pro editorial draft summarises the cited RHS cultivar profile. Check the source and adjust cultivation decisions for local conditions.RHS cultivar profile
1 - Overview
‘Green Magic’ is a hardy biennial cultivated as an annual vegetable. It is grown for rich green edible heads with a sweet flavour and is described as a reliable, high-performing calabrese cultivar. The crop guide identifies it as early maturing, with dense main heads followed by side-shoots.
The exact plant profile also records good resistance to white rust. This combination of early cropping, appealing head colour and flavour, and some disease resistance makes it a practical choice for a dependable summer-to-autumn harvest.
2 - Size
- Ultimate height
- 0.1–0.5 metres
- Ultimate spread
- 0.1–0.5 metres
- Time to ultimate size
- 1 year
The plant completes its useful crop within one growing season. Allow room within the stated spread for a dense central head, open foliage and the side-shoots that appear after the first cut.
3 - Growing conditions
- Suitable soils
- Loam and sand
- Moisture
- Moist but well-drained or well-drained
- Soil pH
- Neutral or alkaline
Choose fertile soil that holds sufficient moisture for uninterrupted growth but does not remain waterlogged. The profile favours neutral to alkaline ground, avoiding the acidic conditions associated with increased club root risk.
4 - Position and hardiness
- Light
- Full sun
- Aspect
- South- or west-facing
- Exposure
- Sheltered
- Hardiness
- H3 — hardy in coastal and relatively mild UK conditions, while normally completed as an annual vegetable crop
A sunny, sheltered plot supports the early, dense heads for which ‘Green Magic’ is selected. Firm soil and protection from wind become increasingly important as each head gains weight.
5 - Colour and seasonal interest
The live profile supplies no individual seasonal colour entries. Its description records rich green edible heads, while the parent crop guide notes that the dense main head is followed by further green heads on side-shoots.
6 - Botanical details
- Family
- Brassicaceae
- Native to Great Britain and Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump-forming
- Name status
- Accepted
Genus
Brassica includes annual, biennial and perennial plants, most upright with alternate and often glaucous leaves, long taproots and clusters of cross-shaped yellow or white flowers. Many species have been bred as food crops, including cabbages, turnips, mustards and oilseed rape.
7 - How to grow
Cultivation
Grow ‘Green Magic’ in full sun in fertile, firmly compacted, non-acid soil. Sow from March to June, placing seed 1cm deep at 30cm spacing. Maintain even growth and cut the dense central head before its buds begin to open, then retain the plant to produce its later side-shoot crop.
Propagation
Propagate by seed using standard indoor or outdoor vegetable-sowing methods.
Pruning
No pruning is required. Cutting the edible main head at maturity encourages useful side-shoots rather than serving as ornamental pruning.
Pests
The profile lists possible damage from birds, cabbage caterpillar, cabbage whitefly, cabbage root fly, cutworms, flea beetle, mealy cabbage aphid, slugs and snails, and swede midge. Fine insect-proof mesh, firmly closed around the crop, excludes many of these pests.
Diseases
Possible diseases include black rot, club root, downy mildew, grey mould, leaf spot and white blister, although the overview records good resistance to white rust. Use rotation, firm non-acid soil, suitable spacing and clean transplants as preventive measures.