Regular checks to beat the blight

THE Botanic Garden is looking stunning at the moment. We plant a mix of edible crops and ornamentals, and at this time of year the flowers are in their prime. The sweet peas, scabious and calendula are all in full bloom.

We plant ornamentals amongst the vegetables and fruit for a variety of reasons: they attract pollinating insects, vital in a vegetable garden. The flowers may also confuse pests, distracting them from the crops. They also look beautiful and make working in and visiting the garden an even more pleasurable experience.

One of the major skills in edible gardening is learning to be very observant to small changes. Pests and diseases can easily ruin entire crops so vigilance is important. We spotted potato blight on our crop last week so took action immediately.

This is a very common disease that has affected many gardens this year because of the warm, damp conditions. Healthy looking potato plants turn into a brown soggy mess almost over night. Blight starts in the leaves and can spread to the tubers. Affected tubers may be firm at first but soon become rotten in store.

The first sign of blight is dark patches on the leaves and a fine white fungal growth may be seen on the underside. The leaves and stems soon shrivel and collapse.

What to do:

• When the plants become badly infected cut off the foliage to ground level.

• Collect up all the debris, ideally it should be burned rather than composted.

• The potatoes can be dug up and eaten fresh.

• If you want to try to store the potatoes leave them in the ground for two weeks for the skin to harden before digging them up.

• Ensure you lift all the potatoes as any that are left in the soil will resprout and spread the disease the following year.

A crop rotation system will reduce the risk of infection. The principle of crop rotation is to grow specific groups of vegetables on a different part of the plot each year.

Jenny Foulkes is edible gardening project manager at the Royal Botanic Garden Edinburgh