ASK DIARMUID

QI have a lime tree which isn’t looking so great. I put it outdoors for summer and it has produced some limes. I’ve already re-potted it once – should I do so again?

Juliette A Yes, your tree does look a bit poorly. I think it has mealybug – these are insects covered in white which suck the sap from plants, so your first job is to give the shrub a good wash. Remove all these insects and keep an eye out for them in future.

If possible, it’s good to re-pot annually in March as citrus are hungry plants and fresh compost is best.

Add horticultural grit to the compost to keep it free draining. I’d also give it a good pruning in spring to encourage a bushy shape – you can cut back quite hard.

Finally, it’s time to take it back indoors before the nights get too cold. Keep it somewhere cool over winter as most houses are too dry and hot.