ASK MONTY

QHow should I prune a fan-trained peach tree that is attached to a garage wall? Margaret Thompson, Lutterworth, Leics

APeach trees produce fruit on growth made the previous summer, so prune by cutting old wood back to a vigorous new shoot and tie this in to grow and replace the old section. Also, remove crowded growth or shoots growing away from or into the wall. Do this in mid-summer, immediately after harvesting any fruit.

My lawn is littered with worm casts. How can I cure the problem?

Deanna Elliott, Reading, Berkshire

QAWorm casts are a good sign that your soil is healthy. The best way to deal with them is simply to brush them – when dry enough – back into the grass.

QI have a pot of alstroemerias and a container of penstemons. When should I cut both back, and by how much? Hilda Micklewright, Charlwood, Surrey

AAlstroemerias (right) grown indoors – a greenhouse or conservatory is ideal – need generous 5ltr pots filled with good peat-free compost. Water well and feed with liquid seaweed once a week.

Do not cut them but pull them from the root. Penstemons should be left uncut but supported until April, then cut back very hard. New shoots will soon appear.

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