GARDEN GURU

Q I planted an apple and plum tree four years ago, training them as fans against a north-facing wall. I prepared the soil prior to planting, and fertilise and water well every year. Neither has produced any fruit. What am I doing wrong? Ray Jones

A I think this is simply a matter of location – some apple varieties are fine in semi-shade, but most apples, along with plums, need warmth and sunshine to thrive.

Q A mysterious shrub appeared in my garden two years ago. It is currently 5ft tall, deciduous with finely divided leaves. Do you know what it is? Adam Spicer

A Your puzzling plant is a type of elder, or sambucus. It’s certainly not unusual for seedlings to pop up from seeds spread by birds. However, as yours is more of an ornamental form, I wonder whether this is from a sucker that has escaped under the fence from next door?

Q I planted a Blechnum brasiliense ‘Volcano’ last year but lost it in late winter. How can they be protected? Jane Allen

A These ferns are highly desirable for their freshly emerging red fronds, but they really hate a cold snap – the best I’ve ever seen were grown undercover at Edinburgh Botanic Garden. I would suggest packing the plant with straw and then surrounding with a fleece cage. Place a plastic sheet over the top to prevent the crown getting damp.