Compost mix for cherry?

[Raindancer411]

Hi All

The boyfriend and I are waiting on a house purchase to go through but we have brought a cherry tree to go in when we finally get it all sorted. Thing is the tub that the cherry is in is no longer sufficient for the tree now it is in leaf and I have brought a bigger tub to temporarily put it in until we can plant it in the ground. I have read somewhere that you need a john innes 3 mix. Is this true or can it just go in multicompost with some shingle to help with drainage?

[FB.]

I find that plants transplant more easily if they are grown in a 50:50 mix of compost and soil. The soil is less nutritious and makes the plants get into the habit of growing stronger roots and more actively searching for nutrients - which means the roots get established more quickly after planting because they're partly used to having to work harder.
I don't bother to arrange "drainage" since the main problem with potted outdoor plants is managing to keep the soil damp enough. I'd just go for the compost:soil mix. I wouldn't get too fancy with the compost, but if you want to give your tree the best, then JI3 - as you suggest - is a good choice.

If you re-pot it now with a complete change of the compost (i.e. the tree becomes completely bare-rooted), you will damage the roots, which carries a small chance of killing the tree if you neglect to water it in the first few weeks after changing the compost.

If you must re-pot the tree, dislodge the outermost inch of the existing compost and untangle any circling roots, then put into a new pot with a compost:soil mix around the existing rootball. Don't be afraid to damage some of the outer roots when untangling, since it is better to damage a few and manage to untangle the outer roots than it is to have the outer roots circle and strangle the tree in a few years time. In fact, I seem to find that a little bit (but not too much!) of outer root damage makes the plant grow stronger roots in response - just like a pruned tree sends out three branches to replace the one that was cut off.

Keep a close eye on it and keep it well watered after re-potting a growing tree - and give extra water if the leaves start to droop.

The best time to re-pot fruit trees is December-February, when the whole tree is dormant.