Posted: 22/03/2016 at 17:35
I love crab apples - the blossom seems to last for much longer than regular apple trees and doesn't blow away at the first gust of wind. For this reason they act as excellent cross pollinators for almost all eating apple trees if you wanted to include a regular apple tree in your garden.
The crab apple fruit itself - whilst unpleasant to eat raw - does make excellent crab apple jelly.
In terms of which crab apple to choose - my experience is:
John Downie - pretty and large fruits but very susceptible to disfiguring scab and the birds usually finish the fruit by October.
Everest - usually smothered in fruit - orangey colour. Birds and squirrels usually finish the fruits early to mid winter.
Red Sentinel - beautiful bright red fruit - the birds don't usually finish this one off until late winter.
There are lots of others but these are the ones I have.
You could also consider a hazel / cob nut tree if you like nuts and want your garden to be productive. Mine are probably 15 - 20 years old and are about 4m high. A denser canopy - but it can be coppiced if it starts to cast too much shade.
BTW - I'm also on clay soil so these should be ok for you.