protectedsoil
Polytunnel
A hooped frame covered in polythene. Cheaper per square metre than glass and covering more ground, at the cost of less light and a cover that needs replacing.
What this changes about growing
- Behaves much like a greenhouse for crop purposes; most guidance transfers directly.
- Retains less heat overnight than glass, so it protects against frost less well than its daytime warmth suggests.
- Large air volume and end-to-end ventilation make it easier to keep cool than a small greenhouse.
What GrowingHQ has assessed in it
Only plants with an actual assessment appear here. A plant that is absent has not been ruled out — it has not been looked at for this method.
| Plant | Suitability | What it needs |
|---|---|---|
| Aubergine | Well suited | |
| Basil | Well suited | |
| Beetroot | Well suited | For early and late crops. |
| Broad bean | Well suited | For an early start in cold districts. |
| Broccoli | Well suited | Chiefly for raising transplants and for early calabrese. |
| Cabbage | Well suited | |
| Carrot | Well suited | |
| Chard | Well suited | |
| Chicory | Well suited | |
| Chilli pepper | Well suited | |
| Chives | Well suited | |
| Cucumber | Well suited | Vertical support |
| Endive | Well suited | |
| Fennel | Well suited | |
| French bean | Well suited | Extends the season at both ends and helps in cold districts. |
| Kale | Well suited | For tender baby leaves in winter rather than for the standing crop. |
| Lamb's lettuce | Well suited | |
| Land cress | Well suited | |
| Lemon balm | Well suited | |
| Lemongrass | Well suited | |
| Lettuce | Well suited | Extends the season to nearly year-round. |
| Marjoram | Well suited | |
| Melon | Well suited | Hand pollination; Support for the fruit |
| Mint | Well suited | |
| Pak choi | Well suited | |
| Parsley | Well suited | |
| Pea | Well suited | For early sowings and for pea shoots. |
| Peach | Well suited | Hand pollination |
| Radish | Well suited | For very early and very late sowings. |
| Raspberry | Well suited | Used commercially to extend the season and keep rain off the fruit. |
| Rocket | Well suited | |
| Savory | Well suited | |
| Shiso | Well suited | |
| Sorrel | Well suited | |
| Spinach | Well suited | Extends both the autumn and the spring crop substantially. |
| Spring onion | Well suited | |
| Strawberry | Well suited | Advances the crop by weeks and keeps rain off the fruit. |
| Sweet pepper | Well suited | |
| Thai basil | Well suited | |
| Tomato | Well suited | Ventilation at both ends |
| Turnip | Well suited | |
| Vietnamese coriander | Well suited | |
| Apricot | Workable | |
| Borage | Workable | |
| Cauliflower | Workable | |
| Celeriac | Workable | |
| Celery | Workable | |
| Chamomile | Workable | |
| Chervil | Workable | |
| Coriander | Workable | Extends the season at both ends. |
| Courgette | Workable | Space — one plant fills a lot of tunnel |
| Curry leaf | Workable | |
| Dill | Workable | |
| Fig | Workable | |
| Garlic chives | Workable | |
| Grape | Workable | |
| Hyssop | Workable | |
| Kohlrabi | Workable | |
| Lavender | Workable | |
| Lemon thyme | Workable | |
| Lemon verbena | Workable | |
| Passionflower | Workable | |
| Potato | Workable | |
| Rhubarb | Workable | |
| Rosemary | Workable | |
| Runner bean | Workable | |
| Sage | Workable | |
| Salad burnet | Workable | |
| Sweetcorn | Workable | |
| Tarragon | Workable | |
| Winter savory | Workable | |
| Winter squash | Workable | |
| Apple | Marginal | |
| Asparagus | Marginal | |
| Blackberry | Marginal | |
| Blackcurrant | Marginal | |
| Blueberry | Marginal | Used to extend the season and keep birds off. |
| Brussels sprouts | Marginal | |
| Cherry | Marginal | |
| Garlic | Marginal | |
| Globe artichoke | Marginal | |
| Gooseberry | Marginal | |
| Leek | Marginal | |
| Loganberry | Marginal | |
| Lovage | Marginal | |
| Onion | Marginal | Chiefly to keep the crop dry while it ripens and dries. |
| Oregano | Marginal | |
| Parsnip | Marginal | |
| Pear | Marginal | |
| Plum | Marginal | |
| Pumpkin | Marginal | |
| Quince | Marginal | |
| Redcurrant | Marginal | |
| Shallot | Marginal | |
| Swede | Marginal | |
| Tayberry | Marginal | |
| Thyme | Marginal | |
| Whitecurrant | Marginal | |
| Jerusalem artichoke | Not suitable |
Ready-made lists from this group
Built from the same assessments as the table above, filtered to the question a person standing in front of the structure is actually asking.