EVERYONE loves strawberries but they do need a little love and care for best results. After picking your last strawberry, start tidying up the plants. Give them a haircut by Remove all the old foliage, the runners you don’t plan to use, any straw or mulch mats and weed the entire bed. This clean sweep sounds brutal, but you’re creating the best environment for new growth. Fresh, new leaves will sprout almost immediately and the first stages of next year’s flowers start developing.

This helps keep strawberry crowns healthy, but is only worth doing to one or two-year-old plants. Strawberries are susceptible to attack from many viruses and fungi. As a result, old plants become tiny, with small, crinkly, mottled leaves. Flowers may have green petals and fruits are usually small and hard.

These pathogens build up in a strawberry bed within a few years. They are spread by aphids and leafhoppers or through the ground by nematodes, such as eelworms, or in soil water.

The scale of this devastation was first seen in the Clyde valley in 1921. After the Great War, growers had been encouraged to produce strawberries and rasps, but three years on, many of their plants turned yellow and died. Scientists found the waterborne disease, red core, Phytophthora farrago, had attacked and killed plant roots.

Consequently, no-one could grow these fruits in Lanarkshire, so the whole operation was transferred to Perthshire and Angus, where it continues to this day.

Immediately after the outbreak, strict rules were introduced to ensure clean, certified stock. So, if buying strawberry plants, only go for fully certified plants and don’t take a gift of young plants from friends.

Due to the fact this build-up of pathogens is inevitable, strawberries should be grown in a fresh bed after three years and be rotated round the garden, like vegetables. Some pathogens persist for up to 12 years, so rotate the crop round four plots, every three years.

Strawberries should follow brassicas, like broccoli, where the soil will still be fairly rich in nutrients. Or they could come after peas or broad beans, where the ground has enjoyed a boost of extra nitrogen. Avoid the tattie patch or a tomato bed, because these crops can share the same pathogens.

Rather than buying new plants, you may want to use runners from your present bed of strawberries. As well as producing seeds, the plants spread by throwing out a bewildering mass of runners. Unchecked, they’d take over a huge area, bed, path, anywhere, within a few brief weeks.

To manage this potential jungle, select vigorous one or two-year-old plants as these should still be disease-free. Choose one or two sturdy runners from each plant and snip off the rest. Since each runner keeps growing, producing a series of small potential plants, cut the growing shoot immediately after the first plantlet.

The baby plant draws nutrients from the mother crown to allow it to develop tiny roots. To help this process, peg the runner to the soil and once the new strawberry is established, cut the umbilical chord with its parent. I let the new plant develop in a small pot, rather than the open ground as this makes transplanting a bit easier.

Either plant out the new strawberries in autumn or the following spring, depending on when the space is available for them. Autumn-planted specimens establish a strong root system before winter and crop successfully the following summer.

If you have to leave planting till spring, the strawberries will have less developed roots, so you’ll end up with a smaller harvest. When I have to delay transplanting like this, I prefer to remove any flowers the first year. This way, I end up with stronger, more productive crowns the following year.