[dmg]

This season I would like to try doing a lot more winter produce but I get confused of what time to sow and plant out after the summer crops. I am doing the following this year.
Plot A potatoes mostly earlies (previous peas) size 30 x 6 m
Plot B Peas/Beans (previous onions) 30 x 5m
Plot C 2 separate beds sweet corn and beetroot (just grass previous) 1 x 3m
Plot D squashes/pumpkins (previous potatoes)
New Raised bed 1 onions 1.2 x 1.2m
New raised bed 2 onions 1.2 x1.2m.
What would be the best to follow at the end of each crop, I will also like to try a bed or 2 with some green manure where is best to put them. I also have white rot on the plot hence the raised beds.

Thanks
Dmg

[BabbyAnn]

It depends on the crop as to when you sow - now I don't know about your location being much further north, but mine are roughly:

parsnips - late March - mid-April
leeks - April
swede - May
sprouts - mid-March
winter cabbages - March-June (depends on variety)

Most of the early sowings are done indoors then moved outside or under cover and repotted as they get bigger.  A lot depends on the weather - you don't want to molly coddle brassicas in a heated greenhouse, but then they are not going to do very much outdoors if the temperatures are still sub-arctic!

Parsnip can easily take 3 weeks or more to germinate (quicker to chit first) so there's always the worry that you might need to consider another sowing and then it starts getting a bit late.  Parsnip probably do better sown direct for nice straight roots but soil temperatures can seriously affect germination, but if sown indoors, put them in long cardboard/paper tubes filled with compost/soil that you can then plant out whole as soon as they start to show, to avoid disturbing the tap root which grows long very quickly.  So in this case, you should have a bed ready prepared in spring.

Leeks might need some protection to grow on (DD is the expert for advice  ) but they don't need to be planted out until about late June - usually a good crop to follow early potatoes provided they are ready (a long cold spring can delay things in the ground) but I find leeks are quite hardy and can hold on a little longer providing their roots are in a good depth of soil.

Cabbages and sprouts - I pot on then plant out about May - mid-July.  I like them to have a good root ball before planting, but not pot bound (as root restriction tends to carry on in the ground and not good anchorage especially in strong winds)