Welcome to my potting shed! This is the column where I’ll share all my gardening hints and tips – and I’ll try to answer any queries you may have.

QQI’ve heard that there’s a plant that repels midges. Can you tell me what it is? – Donald Elder, Aberfeldy.

AAOil from Eucalyptus citriodora “Lemon Bush” is used in the production of citronella candles. Plants can be difficult to get hold of but seed is readily available. Bring indoors during the winter and replant outside the following spring.

Place saucers beneath houseplants, fill

with gravel and keep moist to help irrigate plants during hot weather.

QQA couple of years ago, I planted peachcoloured foxgloves but now I’ve only got purple ones in the garden. What’s gone wrong? – Lisa McMaster, Alloa.

AAYour cultivated foxgloves have crossed with the wild variety. If you want to keep to one colour theme, remove all purple foxgloves and plant a fresh selection of your chosen varieties.

Split up supermarket herbs and repot

into fresh compost for bigger, stronger plants.

QQHelp, in the last few weeks my carpet of ajuga has disappeared. There are few slugs in my garden, so where has it gone? – Olivia Barrett, Edinburgh.

AAA mix of hot weather and scorching sun is the most probable cause. Ajuga does best with some shade and while it doesn’t like to be permanently wet, it should also not be allowed to dry out.

Remove strong-growing invasive weeds

from cracks in walls and paths before the roots can damage the masonry.

QQWhat’s gone wrong with my lupins? They are covered in horrible grey insects. – T Hannan, by email.

AAThis is lupin aphid, a truly dreadful pest. There is no easy way to control these aphids, and spraying while plants are in flower is harmful to flying insects. The bad news is that lupin aphid remains on the host plant throughout the winter, so I’m afraid the only real solution is to dig up and destroy affected plants.

Keep watering camellias throughout the

summer as next year’s flower buds will soon start to form.

QQMy sister in Alicante has offered to bring me rosemary from her garden. Are there any restrictions on bringing it into this country? – Mhairi Watson, Beith.

AAThe Alicante area has been hit by an outbreak of the Xylella pathogen. Rosemary is a host, so your sister should leave it in Spain.