As examples of what can be done and which I do regularly.
We sow cabbage Spring Hero in late August and space out to 1 per pot. They stand somewhere cool, we have a flowhouse which is a modified polytunnel with net sides. When a polytunnel is cleared in autumn they are planted out for a spring crop, with correct management they will give a succession of cabbages right until cleared to make way for e.g. cucumbers or aubergines in the summer. They fill the 'hungry gap' very nicely.
We also raise Japanese onions from seed in the autumn, thin down to 3 or 4 per pot and plant outside when the soil is workable in spring. Thos gives a summer crop of bulb onions before the maincrop in late summer.
Polytunnel
Moderators: KG Steve, Chantal, Tigger, peter
Ian
Good to see a posting from Scotland. With a big tunnel you have scope to experiment with whatever you fancy - and it's always good to experiment - keeps the interest alive and helps us to learn.
I'm further North than you but nearer the coast. I have had a small tunnel for the last 20 years (10 by 15 ft.) and in order of priority these are the crops that have been most worthwhile:
1. sweet corn - always good whatever the summer
2. spring cabbage - always ready for Easter
3. lettuce - sown indoors in early Feb.
4. spring onions - sown indoors early Feb.
4. raddish - sown in tunnel in Feb.
5. courgettes - sown indoors and planted March
6. tatties - plant early March - cover if necessary
7. peas - you can sow in Nov. Better to sow in pots indoors in late Jan. and plant out when plants are a few inches tall. Meteor best so far.
8. pumpkins - but not always reliable here.
9. tomatoes - they have always been OK to good - I only put them last because I now have a greenhouse where they really do beter.
The tunnel is the best investment I ever made - good luck!
Chris
Good to see a posting from Scotland. With a big tunnel you have scope to experiment with whatever you fancy - and it's always good to experiment - keeps the interest alive and helps us to learn.
I'm further North than you but nearer the coast. I have had a small tunnel for the last 20 years (10 by 15 ft.) and in order of priority these are the crops that have been most worthwhile:
1. sweet corn - always good whatever the summer
2. spring cabbage - always ready for Easter
3. lettuce - sown indoors in early Feb.
4. spring onions - sown indoors early Feb.
4. raddish - sown in tunnel in Feb.
5. courgettes - sown indoors and planted March
6. tatties - plant early March - cover if necessary
7. peas - you can sow in Nov. Better to sow in pots indoors in late Jan. and plant out when plants are a few inches tall. Meteor best so far.
8. pumpkins - but not always reliable here.
9. tomatoes - they have always been OK to good - I only put them last because I now have a greenhouse where they really do beter.
The tunnel is the best investment I ever made - good luck!
Chris
Chris
Thank you, Allan and Chris, for most helpful posts. I've been a keen gardener for a long time but the focus of my passion has been on things other than veg. I did have a big greenhouse at one point but I mainly grew tomatoes, peppers and melons. I'm fairly new to veg. and certainly to growing them under cover. I've got the Salt book, the Joy Larkcom, and various others. While the Salt book is undeniably good, I think there's still a need for a more comprehensive work on polytunnel growing on a hobby scale. Joy Larkcom Under Plastic, sort of thing 
Apart from seeking to know what veg. succeed under plastic,(by the way, you don't grow winter-hardy salads, Chris? Have you tried and failed, or what, may I ask?) I'm preoccupied with arrangements to allow me to sow in heat and then to plant out, again with artificial heat,all this in order to get early-ish crops of, e.g. tomatoes, peppers, squashes. For various reasons I don't want to have a free-standing, separate greenhouse. I thought about one of those cheap plastic tunnels (about 10'x 6' ) you see in Kay's Horticultural or, currently, on eBay, or even an 8'x6'Hall's greenhouse the idea being to erect it inside the polytunnel and heat it as a place where seedlings could be grown on, to be planted in the tunnel itself when outside temperatures had reached a level at which protection could be effected with the use of fleece . As a Scots gardener, Chris, do you consider such an arrangement to be worth my while considering? I hope this question isn't so closely linked to my personal circumstances as to be of little interest to others. If it IS, please ignore it!
Apart from seeking to know what veg. succeed under plastic,(by the way, you don't grow winter-hardy salads, Chris? Have you tried and failed, or what, may I ask?) I'm preoccupied with arrangements to allow me to sow in heat and then to plant out, again with artificial heat,all this in order to get early-ish crops of, e.g. tomatoes, peppers, squashes. For various reasons I don't want to have a free-standing, separate greenhouse. I thought about one of those cheap plastic tunnels (about 10'x 6' ) you see in Kay's Horticultural or, currently, on eBay, or even an 8'x6'Hall's greenhouse the idea being to erect it inside the polytunnel and heat it as a place where seedlings could be grown on, to be planted in the tunnel itself when outside temperatures had reached a level at which protection could be effected with the use of fleece . As a Scots gardener, Chris, do you consider such an arrangement to be worth my while considering? I hope this question isn't so closely linked to my personal circumstances as to be of little interest to others. If it IS, please ignore it!