Cropsy
All growing guidesOn the balcony

Growing spinach in a trough

Spinach is the vegetable where timing matters more than care. Sow in May and it bolts during the first warm week, giving you nothing. Sow in March or late August and you have troughs full of leaves within six weeks. That makes it the perfect crop to open and close the season with.

At a glance

Light
4 hours of light, prefers cool conditions
Pot depth
Trough 20 cm deep
Sowing
March to May and August to September
Harvest
6 to 8 weeks after sowing
Water
Evenly moist
Level
Easy

Sowing at the right moment

Sow two centimetres deep, five centimetres apart. Spinach germinates best at ten to fifteen degrees — cooler than most vegetables, and exactly why March and September are its months.

You can skip the June and July sowing altogether. With long days and heat the plant almost always bolts before there is anything to pick.

Care

Keep the compost evenly moist. To spinach, drought is the signal to flower, and once it makes that switch the plant does not come back.

An east-facing balcony often works better than south: morning sun and a cooler afternoon delay bolting by weeks.

Harvesting

Pick the outer leaves once they reach palm size and leave the heart, just like loose-leaf lettuce. That gives three or four harvests from the same plant.

To finish in one go, cut the whole plant two centimetres above the compost. A spring sowing will often reshoot once more afterwards.

Common mistakes

Sowing in May or June and wondering why the plant shoots straight up. That is not a care mistake but a calendar one.

Sowing too densely gives long floppy stalks with small leaves. Five centimetres apart really is the minimum.

Frequently asked questions

Why does my spinach bolt?

Long days, heat or drought — usually all three at once. Spinach is a cool-season crop: sow March to May or from late August, and skip midsummer.

Can spinach stay outside over winter?

A late-September sowing overwinters well in a sheltered trough and resumes growth in February. Keep the trough against a wall, out of the wind.

How much does one trough yield?

A sixty-centimetre trough gives roughly a large salad bowl of leaves per harvest, three or four times per sowing.

Updated on 2026-08-25

Plan it in Cropsy

Cropsy works out pot depth, light and sowing dates for your own spot and puts the reminders in your calendar.

Discover Cropsy

More growing guides