GARDENING: Time to sow the first seeds for summer | Brian Kidd

But first we need some warmth otherwise the seeds won’t germinate.

Begonia semperflorens are some of the best flowers for summer displays because, if sown now, they will be in flower when planted into the garden during the third week in May and will still be in full bloom until the winter frosts arrive.

An electric plant propagator is a very good investment and garden centres have a great range.

They consist of a heated base with a plastic dome over the top with knobs on the front for you to twiddle!

Plug in and switch on the propagator 24 hours before sowing seeds so the temperature is about 15C (60F) and the seeds can the be sown in a seed tray.

Choose either John Innes seed compost or a loamless universal mixture.

Fill the container to within a quarter of an inch from the top and sow the seeds evenly over the surface.

Begonia seeds are like dust and they are expensive, but if mixed and shaken up in a small amount of dry potting sand it helps distribute the seeds more evenly.

Begonias germinate far better if they are in the light. To achieve this, lightly cover the seed tray with fine vermiculite which you will find at your garden centre.

This helps keep the seedlings warm but the granules of vermiculite also absorb moisture and reflect light on to the seeds. This all helps to attain success.

It is very disappointing to watch your seedlings dying off just as they begin to grow. This is caused by a disease called damping off but this fungal disease can be prevented.

Buy a drum of Copper Mixture (Keydell always has this in stock). Follow the directions which tell how to mix the compound with water. Use the strength recommended for copper deficiency.

Pour the mixture into a bowl and place the seed tray in the bowl after sowing the seeds. Leave the seed tray in the mixture until the surface of the compost glistens; this usually takes about 10 minutes.

Leave the tray for another five minutes. This will ensure the mixture will eradicate any fungal spores.

Germination begins about 15 to 21 days after sowing the seeds but the seedlings are notoriously slow to grow. However, if they are given plenty of light this will speed growth.

Simple things like ensuring the greenhouse glass is clean or using a mirror to reflect the light helps them to grow.

If you would like to make an early start in a greenhouse or window ledge without heat, seeds of Chabaud carnations can be sown now, or even seeds of spring-hearting cabbages such as Durham Early. These will be ready to eat in early June.

Cauliflowers seeds sown in the same way will produce magnificent heads in July.

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Autumn-fruiting raspberries can be pruned now. Simply cut off every shoot down to soil level. Once this is completed, spread a four-inch layer of well-rotted manure over the border where they are growing.