Spinach is a quick, easy, and highly nutritious crop that thrives on most UK allotments. Perfect for spring and autumn sowing, it produces tender leaves for salads or cooking. With a little care and good soil preparation, you can harvest fresh spinach for much of the year.
Quick Facts
| Metric | Details |
|---|---|
| When to Sow | March to May and August to September |
| Germination Time | 7–14 days |
| Time to Harvest | 6–10 weeks |
| Ideal Soil | Moist, fertile, well-drained soil |
| Position | Partial shade or full sun |
| Spacing | 10–15cm apart, 30cm between rows |
Preparing the Soil
Spinach prefers fertile, moisture-retentive soil with plenty of organic matter. Dig in compost or well-rotted manure during winter to build up nutrients.
Avoid acidic soils — spinach grows best at a pH between 6.5 and 7.5.
Choose a partially shaded spot during summer to prevent bolting.
Sowing the Seeds
Sow spinach directly where it’s to grow from March to May, or again in late summer for autumn and winter crops.
Make shallow drills about 1.5cm deep and 30cm apart. Sow seeds thinly, then cover lightly with soil and water well.
For continuous picking, sow a small batch every 3–4 weeks.
If slugs or cold conditions are a problem, start seeds in modules and transplant once established.
Watering and Feeding
Consistent watering is key — dry soil leads to bitter leaves and early bolting.
Water regularly, especially during hot spells, and mulch around plants to help retain moisture.
Feed with a liquid seaweed or nitrogen-rich fertiliser every few weeks to encourage leafy growth.
Thinning and Maintenance
When seedlings are 5cm tall, thin them to around 10–15cm apart to allow room for healthy leaves.
Weed gently and keep soil moist.
Remove any yellowing outer leaves to keep plants tidy and disease-free.
Harvesting
Begin harvesting baby leaves from around six weeks after sowing.
Cut outer leaves regularly to promote new growth, or harvest the whole plant when mature.
Spinach is best picked early in the morning and eaten fresh for the best flavour.
Common Problems and Solutions
| Problem | Cause | Solution |
|---|---|---|
| Bolting (flowering too early) | Hot weather or dry soil | Keep soil moist, sow in cooler months |
| Downy mildew | Damp, still air | Space plants for airflow, water at soil level |
| Slugs and snails | Feeding on young leaves | Use organic slug deterrents or traps |
| Yellow leaves | Lack of nitrogen | Feed with balanced fertiliser or compost tea |
Companion Planting Tips
Spinach grows well alongside strawberries, radishes, and brassicas.
Avoid planting next to potatoes or tall beans that may shade it too heavily.
It also makes an excellent undercrop beneath taller plants.
Using the Allotment Planner Tool
Plan your spinach beds using the Allotment Planner tool to manage spacing and succession sowing.
You can also visualise companion plants and crop rotation to keep soil healthy and productive year after year.
FAQs
When should I plant spinach?
Sow in early spring or late summer to avoid bolting in hot weather.
Can spinach grow in shade?
Yes — partial shade helps prevent bolting and keeps leaves tender.
How long does spinach take to grow?
Around 6–10 weeks, depending on the season and variety.
Should I harvest spinach leaves individually or whole?
You can do both — pick outer leaves regularly or harvest the whole plant when mature.
What are the best spinach varieties for allotments?
‘Perpetual Spinach’, ‘Medania’, and ‘Amazon’ are reliable, hardy choices for UK conditions.