
Vegetables · Temperate
Onion
Amaryllidaceae
At a glance
- Plant spacing
- 10 cm
- USDA zones
- 3a–9b
- Frost-sensitive
- no
- Growth duration
- 20 weeks
Which beds suit?
- Sun (prefers)
- full sunAlso okay:partial shade
- Soil (prefers)
- sandyAlso okay:loamyraised-bed mix
- Drainage (prefers)
- very free-drainingAlso okay:normal
Seed & start
Either works
Direct sow works; pre-culture gains 4–6 weeks head start.
Stachi's tip
Plant onions as sets, don't sow — sets are far easier than seed. Plant March/April, harvest August/September. Let the skin dry well before storing — otherwise they rot in the pantry.
The plant's year: sowing, transplanting, harvest
Sowing
Transplanting
Harvest
Good neighbours
Arugula
Broccoli
Broccoli raab
Carrot
Chamomile
Chard
Cucumber
Dill
Kale
Kohlrabi
Lettuce
Mizuna
Pak Choi
Parsley
Pepper
Pumpkin
Tomato
Wild strawberry
Zucchini
Traditional recommendation. Rarely studied under controlled conditions — treat it as experience, not law.
Avoid these neighbours
Traditional recommendation. Rarely studied under controlled conditions — treat it as experience, not law.
Good pre-cultures
Stachi has no specific pre-cultures recorded.
What comes after Onion?
When the bed frees up, the season is usually not over. We worked out what still fits afterwards — with time windows and reasons.
See follow-on crops for Onion →Sources
- Kreuter, Bio-Garten
- Kosmos Gartenkalender
- LLM-Baseline-Intercrop
- LLM-Baseline-2026-05-09 yieldKg
- LLM-Baseline-2026-05-10 family-zehrer
- LLM-Baseline-2026-05-10 sun-soil-drainage
Where these figures come from
- Timing
- Horticulturally established — consistent across the cited standard works.
- Spacing
- Horticulturally established — consistent across the cited standard works.
- Companion planting
- Traditional recommendation. Rarely studied under controlled conditions — treat it as experience, not law.
- Crop rotation
- Traditional recommendation. Rarely studied under controlled conditions — treat it as experience, not law.
- Yield
- Limited evidence. This value is not backed by a specialist source — treat it as a pointer.
Sources: Kreuter, Bio-Garten · Kosmos Gartenkalender · LLM-Baseline-Intercrop · LLM-Baseline-2026-05-09 yieldKg · LLM-Baseline-2026-05-10 family-zehrer · LLM-Baseline-2026-05-10 sun-soil-drainage
Articles about this plant
Brussels sprouts: top the plant now so the sprouts fill out
Your Brussels sprout plants are tall, but the sprouts along the stem stay small and loose? One cut in late September stops the upward growth and sends all the energy into the buds. Now is exactly the right moment for it.
Planting shallots in autumn: the small bulb that earns its keep
Shallots are probably the most overlooked autumn task in the raised bed. Plant now, harvest next July — with barely any effort and no green thumb required.
Planting garlic in September: how to start now for the 2027 harvest
Garlic is one of the few crops where you do the work in autumn and collect the reward in summer. Plant now and you'll have large, aromatic bulbs by next July — or wait until October if you prefer the sweet spot.
Green manure for raised beds: what to sow into the gaps after harvest
Garlic out, peas out, first onions out — by August every raised bed has sudden gaps. Instead of leaving them bare, sow a green manure now: the soil stays alive, weeds don't get a chance, and you start spring with better soil.
Harvesting and drying onions: when to pull them — and how to store them for months
My neighbour Frau Schneider pulled her onions too early last year. Instead of drying out, they started to rot. The difference between an onion that keeps until February and one that turns mushy in October comes down to a single sign.
Garlic from the raised bed: how to tell it's truly ready — and how to store it for a year
Garlic has a small harvest window. Pull it too early and it moulds in three weeks. Leave it too long and the bulb splits open. Here is the one sign I watch for — and how to store it so it lasts until next summer.
Related plants
Products mentioned in this post
- Plantura organic tomato seed set (10 varieties)Open-pollinated, good germination — robust for raised beds.
- Organic tomato seed set, 14 varieties
- Organic heirloom tomato seed set (Demeter, 12 varieties)
- Organic vegetable seed set, 10 varietiesCucumber, tomato, beetroot, broccoli, carrot, chard & more.