Q Will this colourful tree survive hard pruning? KATHERINE WHALLEY, BROUGHTY FERRY, DUNDEE A Your tree is Rhus typina, commonly called stag’s horn sumach. This large, multistemmed shrub is grown for its spectacular autumn colour and has a habit of producing many suckers from the roots, especially in light soils and in drought conditions. It will certainly survive hard pruning, but this will probably encourage more suckers, which could spread some distance from the main plant. Q What would help my poorly potted holly? SONIA TAYLOR, BY EMAIL A Remove your holly from its pot, cut about 2.5cm (1in) of roots and compost from the rootball base with a kitchen knife and replant in John Innes No3 compost. Keep it moist then, when growth starts in spring, apply a weekly liquid feed. To encourage a fuller head of leaves, trim back a few shoots by about half. Then, cut back the new shoots as they emerge on the pruned stems. Q Why are leaves crispy on pieris? J HAWLEY, BOGNOR REGIS A Pieris are generally woodland plants that thrive in moist, humus-rich, acidic soil. Although they don’t need a wet soil and will tolerate periods of drought when mature, the damage to your plant has probably been caused by the extreme heat and drought of last summer. Give it a thick mulch of ericaceous compost now and an ericaceous feed in spring and see if it revives.