Growli

Container guide

Growing spring onion in a pot

Verdict
Ideal in pots
Pot size
12-15 cm (5-6 in) across
Mature size
15-30 cm tall with shanks about 1-1.5 cm thick at picking.

Compost and drainage

Spring Onion needs sharp drainage, so this matters more in a pot than in the ground. Use a free-draining mix (add perlite, grit or bark to standard compost), always pick a container with drainage holes, and never let it stand in a saucer of water.

Watering spring onion in a pot

Containers dry far faster than open ground, so spring onion in a pot needs checking more often than the general guidance of "When the top 2 cm of soil is dry, about every 3-5 days; keep evenly moist" — especially in summer, wind, or a heated room. Check the top few centimetres with a finger rather than watering on a fixed day.

Potting on

Pot on when roots show through the drainage holes or growth slows noticeably — usually every 1-2 years for a plant this size. Move up one pot size only; jumping several sizes leaves wet compost the roots cannot reach, and that is what rots them.

More spring onion care

Growing spring onion in containers — FAQ

Can you grow spring onion in a pot?

Spring Onion is well suited to container growing — at about 30 cm mature it is comfortably pot-sized. A container around 12-15 cm (5-6 in) across gives it room without leaving the compost sitting wet, which is the usual mistake when people over-pot a small plant.

What size pot does spring onion need?

Aim for a container 12-15 cm (5-6 in) across. Pot on when roots show through the drainage holes or growth slows noticeably — usually every 1-2 years for a plant this size. Move up one pot size only; jumping several sizes leaves wet compost the roots cannot reach, and that is what rots them.

What compost and drainage does spring onion need in a container?

Spring Onion needs sharp drainage, so this matters more in a pot than in the ground. Use a free-draining mix (add perlite, grit or bark to standard compost), always pick a container with drainage holes, and never let it stand in a saucer of water.

How often should I water spring onion in a pot?

Containers dry far faster than open ground, so spring onion in a pot needs checking more often than the general guidance of "When the top 2 cm of soil is dry, about every 3-5 days; keep evenly moist" — especially in summer, wind, or a heated room. Check the top few centimetres with a finger rather than watering on a fixed day.