Posted: 26/07/2016 at 21:15
I'd repot them in pots a bit bigger - I'd use a mix of 3 parts John Innes No 3 loam-based compost and one part good quality multi-purpose compost. Check that the stake ties aren't too tight - the trunk needs room to expand.
When you pot them up leave a space of 4" from the top of the compost and the rim of the pot so that when you water you can fill this up, let it soak in and drain away.
And also do everything Pansyface hassuggested.
And give each tree a bucket full of water twice a week in this weather, more if the compost dried out.