Question: Last summer 2013 we planted a Photinia ‘Red Robin’ tree (approx 3m in height). It was planted in an existing heavily clay earth. We used plenty of compost mixed with bonemeal. Sadly, after two months the leaves started dropping off and wilting.The remaining leaves are drooping. Will the Red Robin survive? Should we reposition in another area?
Answer: It sounds as though your photinia has suffered from the effects of weather: dryness in summer and excess water this winter. It may be necessary to replant into a soil that has been improved in structure.
The best way of improving a clay soil is to dig in well-rotted garden compost or farmyard manure over the area to be planted. Then dig the hole to plant. Use the mixture of soil and compost to fill in round the roots. If there is a big dollop of compost in contact with roots, this can act as a sump and water is likely to collect and rot fine roots.
Ensure that the sides of the hole have been roughened up with a garden fork, so that water does not pour down slippery smooth sides and fill it, again risking root rotting. It depends how much the roots have been damaged as to how the plant will recover.
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