Answer: Crab apples are such a good choice of tree for gardens – they will grow in almost any fertile soil and will even put up with a little shade.
The choice is very wide, from growing habit, flower and fruit colour to eventual heights. For a classic red-fruiting cultivar, excellent for making jellies, go for ‘John Downie’, but for pure garden elegance, consider Malus transitoria. It is a small tree with white flowers, followed by branchfuls of small jewel-like orange fruits and striking autumn colour.
The RHS Plant Finder online lists suppliers: rhs.org.uk. The best size of tree to start with is really as small as possible, but a 1.8m tree in a 12 litre container will establish well and is likely to cost around £40.
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Only a few questions per month can be answered. For further advice on handling problems in your garden, visit www.rhs.org.uk/advice/index.asp.