Tomatoes in summer, salads in winter: a polytunnel year
Short answer
In summer a polytunnel is for tender crops: tomatoes, cucumbers, peppers, chillies, aubergines and melons, planted from late April. In autumn, follow them with winter salads, spinach and oriental leaves, and use the spring for early potatoes, carrots and transplants.
Tomato sowing calendar
From the VegLog crop library. Change the frost dates to match your garden.
Last frost around 20 April, first frost around 31 October.
- Sow indoors
- late February to late March
- Plant out
- early May to early June
- Harvest
- mid-July to late October
A polytunnel gives you two seasons in one space. In summer it grows the heat lovers that struggle outdoors in a cool British summer. In winter it keeps salads and leaves cropping when outdoor beds are bare.
Summer: the tender crops
| Crop | Sow | Plant in the tunnel | Pick |
|---|---|---|---|
| Tomatoes | Late February to late March | From late April | Mid-July to late October |
| Cucumbers | Late March to late April | From early May | Late June to late October |
| Sweet peppers | Early February to early March | From early May | Mid-July to late October |
| Chillies | Late January to early March | From early May | Mid-July to late October |
| Aubergines | Early February to early March | From early May | Mid-July to late October |
| Melons | Late March to mid-April | From mid-May | Late July to mid-October |
These are the usual dates for a typical lowland garden in England or Wales. In a well-sealed tunnel you can often plant a week or two earlier, and the crops keep going later into autumn. Space tomatoes about 45 cm apart, peppers the same, and aubergines 60 cm.
Basil and French marigolds grow well between the tomatoes, and dwarf French beans fill any gaps.
Autumn and winter: salads and leaves
As the summer crops finish in October, clear them and plant the winter crops you sowed in August and September:
- Winter lettuce and salad leaves.
- Spinach and chard, which keep producing through mild spells.
- Lamb’s lettuce, land cress, mizuna and mustard, all very hardy.
- Spring onions and a few pak choi.
Water sparingly in winter, as the soil dries slowly, and open the doors on mild days to stop mould.
Spring: an early start
Before the tomatoes go in, the tunnel is ideal for early carrots, radishes, early potatoes in bags and a first crop of salad. It’s also the perfect place to harden off seedlings before they go outside.
Keeping it healthy
- Ventilate every day from spring to autumn. Overheating is a bigger risk than cold.
- Water evenly, ideally in the morning, to prevent splitting fruit and blossom end rot.
- Rotate the tomato and pepper beds with cucumbers each year, or refresh the soil with compost.
- Clean the cover in autumn so it lets in more winter light.
For the tomatoes in more detail, see greenhouse tomatoes, which works the same way in a tunnel, and when to sow cucumbers.
Questions people also ask
When can I plant tomatoes in a polytunnel?
From late April in most of England and Wales, a few weeks before they can go outdoors. Keep fleece handy for cold nights in the first fortnight.
Can I grow cucumbers and tomatoes together in a polytunnel?
Yes, most people do. Cucumbers like more humidity, so put them at the damper end, damp down the path on hot days, and keep the doors open for the tomatoes.
What can I grow in a polytunnel in winter?
Winter lettuce, spinach, chard, lamb's lettuce, land cress and oriental leaves like mizuna and mustard. Sow them in August and September and they crop through winter.
Dates set to your own frost dates
VegLog works out sowing and planting times for your town, then reminds you when each job is due.
