GARDEN GURU

Q

We bought an upright cactus ten years ago that now has several small segments growing from it. Can I take these off to form new plants? Tony Shuker

A

Yes. Segments or pads from bushy, upright cacti root readily. Wearing gloves, gently remove from the main plant and allow the cut end to dry for a week before rooting in gritty compost. You can propagate them all year round but cactus will establish much faster in summer.

Q

I’ve read that stems of alstroemeria flowers should be pulled out of plants and not cut. Is this correct? Sean Courtnell

A

I know gardeners who favour pulling stems as they believe it encourages plants to produce new shoots from the crown. In reality, it doesn’t matter if you cut or pull them. The latter method comes from the cutflower industry, where pulling is the quickest way to harvest.

Q

What are the tiny flies that live in my compost bin? Are they harmful, and should I be worried about them? Camilla Bruce

AThese are fungus gnats, harmless insects that feed on decaying matter. You can reduce their numbers by making sure the lid is kept firmly in place and by turning the compost regularly to bury their larvae.