A little seed. A new beginning.
Seeds In A Cup® — home

Gallery includes shared Seeds In A Cup® brand imagery. Plant-specific packaging may differ.

Seed Germination Kit

Onion Seed Starter Grow Kit

BOTANICAL NAMEAllium cepa

USD 10.99

100 in stock

Onions are the foundation of nearly every savory dish — grow your own for sweeter, fresher flavor.

GERMINATION7-14 days
SUNLIGHTFull Sun (6-8 hours daily)

Have a question about this kit?

Ask our team →
Explore the growing guide

Get to know your plant

A little knowledge.
A better beginning.

The growing details, all in one place.

Germination01

7-14 days

Light02

Full Sun (6-8 hours daily)

Temperature03

65-75F

Hardiness04

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
01

Start growing

Seeds require patience. Keep weed-free as onions are poor competitors.

02

Growing with your kit

Use the Seeds In A Cup® kit to start delicate seeds in a controlled environment before garden transplanting.

03

Propagation

By seed, 'sets' (small bulbs), or transplants.

04

Seasonal growth & harvest

100-120 days from seed. Harvest when tops fall over and turn brown.

05

Growing conditions

Friable, fertile loams with full sun.

06

Weather & tolerances

Frost hardy; sensitive to photoperiod (day length) for bulb formation.

07

Pests & plant health

Onion maggot and downy mildew.

08

Plant safety

Safe for humans; toxic to dogs and cats (causes hemolytic anemia).

09

Botanical features

A biennial bulbous plant grown as an annual. Consists of a subterranean bulb of modified leaves.

10

Varieties

‘Walla Walla Sweet’, ‘Red Burgundy’, ‘Yellow Granex’.

11

Garden & everyday uses

Essential culinary base. long storage life

12

Native range & distribution

Cultivated globally; wild ancestors likely from Central Asia.

13

Conservation

Global staple.

14

Name origins

Latin ‘unio’, meaning unity or one, referring to the single bulb composed of many layers.

15

History

Used by Egyptians as a symbol of eternity and placed in tombs of pharaohs.

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.

Connect the plant to the kit

More ways to grow.

Matched using botanical names and explicit plant mentions in our catalog.

Mentions Onion in the catalog description

Mentions Onion in the catalog description

Mentions Onion in the catalog description

INFORMATION SOURCE

Growing details are supplied in the Seeds In A Cup® product catalog. Follow the instructions included with your specific kit.

Our information standards ↗

Keep your curiosity growing

There’s more to discover.

Explore all grow kits

The growing journal

Read. Learn. Grow.

8 articles matched to this plant.

All Onion articles →