7-14 days






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Onion Seed Starter Grow Kit
BOTANICAL NAMEAllium cepa
USD 10.99
Currently unavailable
Onions are the foundation of nearly every savory dish — grow your own for sweeter, fresher flavor.
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A little knowledge.
A better beginning.
The growing details, all in one place.
Full Sun (6-8 hours daily)
65-75F
Check the directions supplied with your seed variety.
THE PLANT NOTEBOOK
Onion care, from seed onward.
- Botanical name
- Allium cepa
- Common names
- Garden Onion, Bulb Onion
- Family
- Amaryllidaceae
- Genus
- Allium
- Species
- A. cepa
Start growing
Seeds require patience. Keep weed-free as onions are poor competitors.
Growing with your kit
Use the Seeds In A Cup® kit to start delicate seeds in a controlled environment before garden transplanting.
Propagation
By seed, 'sets' (small bulbs), or transplants.
Seasonal growth & harvest
100-120 days from seed. Harvest when tops fall over and turn brown.
Growing conditions
Friable, fertile loams with full sun.
Weather & tolerances
Frost hardy; sensitive to photoperiod (day length) for bulb formation.
Pests & plant health
Onion maggot and downy mildew.
Plant safety
Safe for humans; toxic to dogs and cats (causes hemolytic anemia).
Botanical features
A biennial bulbous plant grown as an annual. Consists of a subterranean bulb of modified leaves.
Varieties
‘Walla Walla Sweet’, ‘Red Burgundy’, ‘Yellow Granex’.
Garden & everyday uses
Essential culinary base. long storage life
Native range & distribution
Cultivated globally; wild ancestors likely from Central Asia.
Conservation
Global staple.
Name origins
Latin ‘unio’, meaning unity or one, referring to the single bulb composed of many layers.
History
Used by Egyptians as a symbol of eternity and placed in tombs of pharaohs.
A closer look
The details
behind your kit.
Full product description
Catalog variants
- SIAC-001-198PAA — USD 10.99 · Out of stock
Shipping & returns
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Good questions grow here
A little more clarity.
How do I grow Onion from seed?
Moisten the included soil, sow your Onion seeds at the depth on the instruction card, keep the planter warm and bright under the humidity lid, and mist until they sprout. Full steps are in your kit.
How long do Onion seeds take to germinate?
Onion seeds typically sprout in 7-14 days at 65-75F when kept warm and evenly moist. Your guide lists the ideal conditions.
Growing details are supplied in the Seeds In A Cup product catalog. Follow the instructions included with your specific kit.
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