Crop type: Cabbages
Brassica oleracea (Capitata Group) ‘Red Jewel’
Common name: Cabbage ‘Red Jewel’
Crop slug: cabbages
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
‘Red Jewel’ is a round red cabbage with an RHS Award of Garden Merit. Broad plants produce large, tightly packed hearts of crisp ruby-red leaves with excellent flavour. Heads can be harvested from July through October, stand well when mature and store well after cutting.
The combination of a substantial spherical head and rich red-purple colour makes this cultivar immediately distinct from the green pointed and Savoy cabbages in the parent guide.
2 - Size
- Ultimate height
- 0.1–0.5 metres
- Ultimate spread
- 0.5–1 metre
- Time to ultimate size
- 1 year
The plant is much wider than it is tall. Give each large head generous spacing so the outer foliage receives full light and the tightly packed heart can develop without crowding.
3 - Growing conditions
- Suitable soils
- Sand, loam and chalk
- Moisture
- Well-drained
- Soil pH
- Neutral or alkaline
Grow in fertile ground with free drainage and consistent moisture during head formation. Neutral or alkaline soil is preferable to acidic conditions where clubroot is more likely.
4 - Position and hardiness
- Light
- Full sun
- Aspect
- South- or west-facing
- Exposure
- Sheltered
- Hardiness
- H3 — hardy in coastal and relatively mild parts of the UK, with protection needed from harder frosts
Use a sunny, sheltered bed. As the crop is harvested from July to October, its lower hardiness is usually less limiting than it would be for an overwintering cabbage.
5 - Colour and seasonal interest
| Season | Flowers | Foliage | Fruit |
|---|---|---|---|
| Spring | — | Green, grey, silver and purple | — |
| Summer | — | Green, grey, silver and purple | — |
| Autumn | — | Green, grey, silver and purple | — |
| Winter | — | — | — |
The live seasonal table records green, grey, silver and purple foliage from spring through autumn. The overview gives the more specific edible-head colour as ruby red. An em dash means no colour is supplied for that field and season.
6 - Botanical details
- Family
- Brassicaceae
- Native to Great Britain and Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump-forming
- Name status
- Accepted
Genus
Brassica includes upright annual, biennial and perennial plants with alternate, often glaucous leaves, long taproots and clusters of cross-shaped yellow or white flowers. It includes cabbages and other important food crops such as turnips and mustards.
7 - How to grow
Cultivation
Grow ‘Red Jewel’ in fertile, moist but well-drained soil in full sun. Sow indoors from February to May and transplant when seedlings carry five or six true leaves. Alternatively, direct-sow from late March, placing seed 1cm deep in rows 23cm apart. Move or thin plants to generous final spacing for the large heads.
Propagation
Propagate by seed, sown indoors or directly outdoors.
Pruning
No pruning is required. Remove only damaged outer leaves and cut the whole head when firm and fully coloured.
Pests
Potential pests include birds, cabbage caterpillars, cabbage gall weevil, cabbage root fly, cabbage whitefly, cutworms, flea beetles, mealy cabbage aphid, slugs, snails and swede midge. Fine mesh and regular inspection help protect the crop.
Diseases
The profile lists possible susceptibility to black rot, clubroot, downy mildew, foot and root rot, leaf spot and white blister. Rotate brassicas and maintain good soil drainage, suitable pH and airflow.