How are your craberry plants doing ?

As @NigelJ has said - they grow in damp, and even boggy ground, so a pot is always going to be difficult. An easier solution is to keep a tray or similar underneath to try and combat the dryness. If you're in a much drier part of the UK, you'll always struggle to keep it hydrated well enough.
Compost is no use - it needs to be a heavier, soil based mix with enough acidity to suit. If it's affected by too much sun - it needs to be somewhere with some shade from the hottest part of the day.
However, if you can't give any plant the conditions it likes - and needs, in order to thrive well, you have to ask yourself - is it really worth growing it?

 

There are in a mix of ericaceous compost with lots of leaf mould. The soil only goes crispy, or shrinks, if they are to dry. I agree with fairygirl that a tray underneath them is the easiest way to keep them moist but I also mulch them.

I think from memory the varieties I have are early black and pilgrim. I don't know if they cross pollinate or not, it might be why I haven't had fruit.

 

im tempted to try again

 

I found a label I bought mine with:

 

Thank you im not sure if I should try again. Every year they just seem to go crispy presumably due to heat.

Did buy this in the UK i notice the website is .eu

 

The Range, they had many of them that year.

 

Can I check did these grow up ? The label says ground cover which is what mine did but your picture looks like a vertical plant

 

They are ground cover but sometimes when you buy them, they clump them together and support them, so they are a bit higher before they flop.

 

Mine in pot, it's "flowing" sideways.