Crop type: Onions
Allium cepa (Cepa Group) ‘Red Baron’
Common name: Onion ‘Red Baron’
Crop slug: onions
This Allotment Pro editorial draft summarises the cited RHS cultivar profile and its linked crop guidance. Check the sources and adjust cultivation decisions for local conditions.RHS cultivar profile
1 - Overview
‘Red Baron’ is an AGM onion for harvesting in mid- to late summer. It forms globe-shaped bulbs with dark-red skins and firm white flesh, each internal layer edged with a dark-red rim. Its strong flavour and dependable keeping quality make it useful both fresh and from winter storage.
Grow it from sets for a quick reliable crop, or from fresh seed for a wider choice of planting method. Full sun, fertile free-draining ground, steady early moisture and a dry ripening period produce the best bulbs.
2 - Size
- Ultimate height
- 0.1–0.5 metre
- Ultimate spread
- 0.1–0.5 metre
- Time to ultimate size
- one year
Space sets 5–15cm apart in rows 20–30cm apart, using wider spacing for larger bulbs. The foliage is compact and upright, but keep enough space for airflow around ripening necks.
3 - Growing conditions
- Suitable soils
- Chalk, clay, loam or sand
- Moisture
- Moist but well drained, or well drained
- Preferred pH
- Neutral or alkaline
Incorporate well-rotted organic matter before planting. Water during prolonged dry spells while roots and foliage develop, then stop once bulbs swell in mid-summer so skins and necks can ripen.
4 - Position and hardiness
- Light
- Full sun
- Aspect
- South- or west-facing
- Exposure
- Sheltered
- Hardiness
- H3
Choose an open sunny bed where foliage dries rapidly after rain. Protect newly planted sets from birds with fleece or netting until rooted.
5 - Colour and seasonal interest
Green cylindrical leaves rise above rounded bulbs through spring and summer. At maturity the papery outer skin is deep red, while cut bulbs reveal firm white layers sharply rimmed dark red. Remove flower stalks immediately because bolted bulbs do not store well.
6 - Botanical details
- Family
- Amaryllidaceae
- Native to Great Britain and Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Name status
- Accepted
Genus
Allium includes bulbous herbs with an onion or garlic scent, cylindrical or strap-shaped basal leaves and star- or bell-shaped flowers in an umbel when allowed to bloom.
Safety
The bulb is edible. Avoid bruising it at harvest, and use damaged bulbs promptly rather than placing them in long-term storage.
7 - How to grow
Cultivation
Grow in a sunny sheltered site in fertile, neutral or alkaline, well-drained soil. Plant sets in early to mid-spring about 2cm deep with the tip just visible. Alternatively sow seed 1.3cm deep from mid-winter to mid-spring.
Keep weed-free, water while establishing and stop watering after bulb swelling. Lift when foliage yellows and falls naturally. Dry for about two weeks with free air circulation before storing somewhere light, cool, dry and ventilated.
Propagation
Propagate by seed or onion sets. Sets are easiest; use fresh seed because onion seed viability declines quickly.
Suggested locations
- Vegetable plot
- Raised bed
- Sunny allotment row
- Large container
- Cottage edible border
Pruning
No pruning is required. Remove premature flower stalks and clear dead foliage at harvest.
Pests
May be susceptible to onion fly. Birds may disturb recently planted sets.
Diseases
May be susceptible to onion downy mildew, onion white rot, onion neck rot and leek rust. Rotation, drainage, airflow and careful curing help reduce losses.