Posted: 06/04/2016 at 16:20
Hi, again, Shirley.......you've done nothing wrong at all, but (IMHO) the Garden Centres should be downright ashamed of themselves for selling these (and other) things without giving guidance.
Normally they throw half a dozen or so seeds into a 9cm pot, water them, stick them somewhere unsuitably warm....next stop the GC. They adopt the same procedure with other things, such as runner beans & peas.
We assume you have half a dozen or so individual plants in each pot and these need to be gently teased apart into individual plants......gently does it, as sweet peas don't like root disturbance.
So now, where to plant them? As said previously, your container is far too shallow for these deep rooted plants, so try to find somewhere in the open ground where the soil has been deeply dug, then replant about 15cm apart.....alternatively, in the deepest pots you can find.
Initially just put a few twiggy sticks around them for support.....we'll talk about more substantial support later if you wish.
It's a shame really, cos you probably only needed to buy 1 or 2 pots.