i have a pauls scarlet for about 7 years. it flowers brilliantly but it never seems to have anchored itself properly. it has always been staked. last year i got a jcb to put down a post to support it to and it has been great but i know from the look of it that it is still not anchored. what can i do? it is about 11 foot tall
The trick is to give enough support to prevent severe wind rocking and further root damage, but to allow enough movement to trigger the tree into trying ot make anchor roots and not just becoming dependent on a strong stake.
Usually staking low down, as you have done is the best trigger for roots, and have three strong stakes and the tree tied in the centre. Be careful to ensure that the ties do not cut the stem bark. Rubber pond liner or folded plastic is very good for that.
Another approach, one that can be used in conjunction with staking, is to reduce the top weight of the tree, and its height, by pruning after flowering to reduce wind heave.
Failing all the above, use three guy wire cables tied at the lowest branches back to 3 strong stakes. This can be a longterm solution. The wires are hardly visible.