Tuesday, 27 June 2017

Growing in the polytunnel through the seasons

Polytunnel in early June
We have now had our 20ft x 8ft polytunnel for 14 months and have done a lot of experimenting with different crops. Since space is at a premium we don't bother growing anything in the tunnel that will happily grow outside such as onions, potatoes and brassicas (and lettuce in summer) or that won't be significantly faster inside than out, such as carrots. Here's what works for us to keep the polytunnel productive all year round:

Permanent residents


The grapevine freshly planted
Because grapes in Scotland is too amazing not to! The roots are planted outside the tunnel and the vine is inside. This makes watering easy (i.e. not generally necessary) and will hopefully give us sweeter grapes.

Lemon verbena

This delicious tea herb (which is also great in gin & tonic) doesn't really work outside here but loves it in the polytunnel. It dies back over winter but sprouts again the following spring.

Summer crops

In the summer, about half the polytunnel is given over to tomatoes since we are in an area prone to potato blight and thus have to grow our tomatoes in containers inside.

Polytunnel in May


The first summer I squeezed 30 of them in, but this year we've scaled back to 17 plants since it is nice to have a variety of things. Some are very early tomatoes (Matina) to start the season as early as possible and then it's a mix of cherry tomatoes, beef tomatoes and normal size heirloom tomatoes in different colours (though black definitely seems tastiest).

Herbs that like it hot

Several varieties of basil, which is a good companion plant to tomatoes, and some lemongrass.

Courgette Latino, harvested in late May


An early one, sown in mid March, that is planted out into the polytunnel in late April and gets to stay there, plus a couple of early sown ones that get planted outside in early May with protection.


We keep our varieties of cucumbers apart and the tunnel is home to the Crystal Lemon cucumbers that look like lemons when they are ripe.

Oriental leaves

Successional sowings of komatsuna and pak choi.

Peppers and chillies

Any leftover plants that don't fit into the conservatory.

Experimental crops

Anything that needs the extra heat. This year, it's chickpeas.


Since it's too windy here for climbing beans (at least above hedge height), we've planted some in the polytunnel, in a spot vacated by early spring salad leaves such as red mustard and pak choi. In July, we'll also sow some dwarf French beans for a late crop.

Overwintering crops

A nice bowl of early broad beans

Broad beans Aquadulce

Sown in the first week in November, the indoor plants beat the outdoor plants by a good three weeks. We had broad beans from mid May onwards. Definitely worth having three or four broad bean plants in the polytunnel!

Peas Douce Provence

Also sown in the first week in November, the peas suffered quite a few casualties, but the remaining plants had peas from April onwards - just enough for a delicious little snack every other day. Next time we'll put these in the middle of the polytunnel to give them a better chance of making it.

Lettuces Valdor and Winter Density

Sown in September and October, these hardy lettuce types were ready to harvest in March. Quite a few were devoured by slugs so beer traps will have a permanent home in the polytunnel next winter. We'll increase the number of lettuces this year since they are all going to be eaten long before the tomatoes can be planted out. Might as well fill the tunnel over the winter!

Hardy salad leaves

Sown in September, hardy salad leaves such as rocket, mizuna, pak choi, red mustard gave us lovely fresh salad in the winter months. The rocket even self-seeded inside the tunnel so that we had a continuous supply throughout the winter.

Early spring crops

Early Wonder beetroot, harvested in early May

Beetroot Early Wonder/Boltardy

Sown in early February and planted out into the polytunnel in March, these were a good three weeks ahead of the outdoor beetroots. The ones we sowed in November bolted so starting them early in the year seems to be the better option and not any slower.

Pak choi

Sown in late February, early pak choi does a lot better under cover and is ready to eat in early May.


The first sowing of lettuces such as Salad Bowl Red, Merveille des Quatre Saisons and Little Gem also goes into the polytunnel, but it's not usually long into spring before the lettuces prefer the cooler outside conditions.

It took us a couple of years to decide on getting a polytunnel in the first place. Having got one, the question of course becomes, "Why didn't we do this sooner?". The increased range of growing options is nice, but the biggest plus is definitely the closing up of the 'hungry gap', when winter crops run out before new season ones are ready, that comes in late spring with outdoor-only growing.


  1. A polytunnel is a wonderful thing! isn't it incredible how you can extend the seasons and fill the hungry gap with what is little more than a sheet of stretched plastic? Your veg all look great. We did used to grow a few indoor potatoes - first earlies planted in Jan/Feb for a May harvest - but maybe not a good idea if blight is a problem. Looking forward to seeing all those tomatoes in a future post.:-)

    1. New potatoes in May - I think we'll just have to try that next year. Normally the blight doesn't hit until early August.


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