Onion
Photos
Beans, peas and corn: remove husks and allow seeds to dry out – this may take a couple of weeks, then remove casings and store.
Pumpkins and melons: seeds need to be washed and set aside to dry for a week or so before …
Last edited on 1 Nov 2026. View history
- 85
- plantings
- 20
- harvests
- 15
- seed packets
Onion facts
Lifespan
Annual
living and reproducing in a single year or less
34 weeks
median lifespan
First harvest expected
36 weeks after plantingLast harvest expected
46 weeks after plantingHeight × spread
1cm × 15cmRow Spacing
20cm median of members' seed packetsGermination
10–15 days median of members' seed packetsDays until maturity
109–217 days median of members' seed packetsWhen to sow
Southern hemisphere
Mar–Aug
Northern hemisphere
Sep–Feb
median of members' seed packets
Grown for
bulb harvested 14 timesWhat are growing degree days?
A plant grows with warmth, not with days. A growing degree day is one day's worth of useful warmth: how many degrees the day's average temperature is above the lowest temperature the crop grows at. Add them up from planting and you know how far along the crop is, whatever the calendar says.
Say that lowest temperature is 10°C. A day averaging 17°C gives 7 growing degree days. A day averaging 8°C gives none, as it is too cold for the crop to grow. That is why the same lettuce takes about 50 days in a summer and 90 in an autumn: it needs the same total warmth either way.
For onion, the FAO EcoCrop database gives a lowest growing temperature of 4°C and a shortest growing cycle of 85 days at its best temperature, about 1233 growing degree days to a first harvest.
Where you've told us where your garden is, we use this and the weather there to predict when your onion will be ready to harvest. We don't use it for how long a plant lives or when it finishes: we go by what members have logged for that.
Growing onions
- Sow seeds in trays 8 weeks before planting out
- Dig compost into the bed 1 week before planting out
- Water regularly at planting out every week
- Weed around the plants 2 weeks after planting out every 2 weeks
- Feed with a nitrogen fertiliser 4 weeks after planting out every month
- Stop watering as the tops fall over 1 week before first harvest
- Lift the bulbs at first harvest
- Dry the bulbs in an airy place 1 week after first harvest
How members grow onions
Sunniness
Loading...
Planted from
Loading...
Harvested for
Loading...
Varieties of onion
Potato Onion
Allium cepa
Pukekohe long keeper onion
Allium cepa
red onion
Allium cepa
California red onion
Allium cepa
shallot
Allium cepa var. aggregatum
spring onion
Allium
Welsh onion
Allium fistulosum
Welsh bunching onion
Allium fistulosum
Photos
Onion crops
Onion plantings
Onion harvests
Onion seeds
Video
Where onions grow
Only plantings by members who have set their locations are shown.
What people are saying about onions
How to save seeds
by shiny,
beans
peas
corn
pumpkins
melons
lettuces
celery
parsnips
carrots
leeks
onions
radicchio
cucumbers
tomatoes
zucchini
capsica
Read more
Planting outdoors & fruit trees
by maco,
Today I transplanted the cabbage and onion seedlings outside and planted seeds for: arugula, garlic (well, cloves, not seeds–forced in the fridge), mesclun salad mix, kale, cauliflower, and …
cabbages
onions
arugula
garlic
kale
cauliflowers
beets
apples
peaches
almonds
plums
Read more
Coming together
by shawnacscott,
This weekend I had two full days to really focus on the yard, and I made the most of it. With the intermittent help of several others over the course of the weekend, I got both easement planter boxes filled with compost and soil, cleaned up and weeded the alley, got the stump pulled from the coni…
lettuces
arugula
mustard
sunflowers
dill
onions
beets
tomatoes
fenugreek
bell peppers
okra
artichokes
mint
lavender
spinach
basils
thyme
parsley
zucchini
peas
calendulas
Read more
Getting ready for spring!
by maco,
I've got seeds either on-hand or ordered for just about everything I'm starting from seed this year. I've been working out what I want to plant, and this is the plan I've come up with for the 72 square feet of my backyard raised beds:
eggplants
garlic
kale
lettuces
onions
oregano
parsley
Hungarian wax peppers
bell peppers
zucchini
yellow summer squash
butternut squash
sweet potatoes
tomatoes
super sweet 100 tomatoes
chamomiles
Read more
This year (2014)
by Mad_Martha,
This year wasn't a particularly good year in my garden. Due to my ill health through spring and summer, the only things that got planted were the potatoes, onions and elephant garlic, all of which were planted either late last year or ea…
potatoes
onions
elephant garlic
Read more
Who's planted onions
- wrdnrd Rivendell — Balcony · UDistrict, Seattle,...
- bokunenjin spring onion Garden · Columbia, MD, USA
- jinty Kitchen garden · Oxford, uk
- shiny The Deck · Wellington, NZ
- CloCkWeRX spring onion A & B - Raised Containers · Rosewater, South...
Onion harvests
-
shiny harvested not specified.
almost 2 years ago
-
shiny harvested not specified.
almost 6 years ago
-
shiny harvested not specified.
about 6 years ago
shiny harvested not specified.
Find onion seeds
View all onion seeds
- Purchase seeds via Ebay
- Sign in or sign up to list your seeds to trade.
Ecological requirements
Data from the FAO EcoCrop database for Allium cepa L.
| Family / Taxonomy | Liliopsida Liliidae Asparagales Alliaceae |
|---|---|
| Optimal temperature | 12 - 25 °C |
| Absolute temperature | 4 - 30 °C |
| Optimal rainfall | 350 - 600 mm/year |
| Absolute rainfall | 300 - 2800 mm/year |
| Optimal soil pH | 6.0 - 7.0 |
| Absolute soil pH | 4.3 - 8.3 |
| Crop cycle | 85 - 175 days |
| Max altitude | 2000 m |
| Life form | herb |
| Life span | biennial |
| Habit | erect |
| Optimal soil depth | medium (50-150 cm) |
| Optimal soil texture | medium, organic |
| Optimal soil fertility | moderate |
| Optimal soil drainage | well (dry spells) |
| Optimal soil salinity | low (<4 dS/m) |
| Photoperiod | short day (<12 hours), neutral day (12-14 hours), long day (>14 hours) |
| Optimal light | clear skies |
Learn more about onions
Resources outside Growstuff.
