PICK THE MONTH

It's usually best to remove strawberry runners before they start to creep along the ground.

If you leave them they will reduce the yield of fruit. If you need runners to produce new plants for next year, pinch off the flowers from a couple of plants, which will encourage them to produce runners at the expense of flowers and fruit.

Peg down the young strawberry plants into small pots of compost. The runner can then be severed once the plant has rooted. Early strawberry crops kept under glass, fleece or cloches, should be uncovered, or the greenhouse doors opened, to give pollinating insects access. Put down slug controls and straw around outdoor strawberries to keep the developing fruit off the soil. The flowers on young strawberries planted this spring are best removed. This allows the plants to build up strength for a good crop next year.

Thin out crowded raspberry canes ensuring there is sufficient air and light between the branches.

This will help reduce disease problems and ensure the plant can ripen all the young fruit to maturity. Hoe off or pull out raspberry suckers appearing between the rows.

Plant out greenhouse tomatoes once the first truss of flowers has set.

You can grow them in soil in the border, but it's often best to use other methods, such as growing-bags, 20cm (8in) pots or growing rings filled with potting compost.

If you find that growing-bags dry out too quickly - and the bottom of the fruit turns black - then cut the bags in half widthways, stand them on end and put one plant in each half. And don't forget you'll need to regularly water, feed and support the plants.