GARDEN GURU

Q The fruits on our plum tree are covered in little brownwhite spots. Is it a type of fungus, and what should we do? Elizabeth Muncaster

AYes, your fruits are blighted by brown rot, a common fungal disease that attacks plums and many other fruit trees. It’s difficult to control, but you should be able to reduce damage next year by removing all infected fruit from the branches and the ground now – throw them in the bin and not on the compost heap. In winter, snip back damaged-looking shoots, disinfecting tools between cuts.

Q Two years ago I planted a calla lily in a large pot. It’s in a sunny, sheltered spot but hasn’t flowered at all. How can I encourage it to bloom?

Denise Wharton

A The plants in the pictures you emailed look healthy, so I wouldn’t worry too much. Make sure compost never dries out completely during the growing season. You don’t mention if you feed your plants, but calla lilies produce leaves at the expense of flowers when overfed with fertiliser that’s high in nitrogen. Feed with a balanced liquid fertiliser in spring but nothing more until they start to flower.

Q Hollyhock seedlings I planted in my garden last autumn didn’t produce flowers this summer. Why is that?

Diane Maynard

A Hollyhocks can take two years to flower. If planted in well-drained soil in full sun, they should produce flower spikes early next summer. Remove any dead leaves before winter.