BRIAN KIDD: on dahlias, cacti and... this week's worksheet

Q: I love growing dahlias but they have a great amount of foliage and not many flowers. Would it be a good idea to split the tubers? BH, Milton.

A: Yes. When you replant the tubers fork into the soil two or three ounces per square yard of sulphate of potash. Your soil is very rich in nitrogen. That’s the reason for exceptional foliage. The potash will balance the nutrients.

Q: My little boy loves cacti. We have tried to grow some from seed without success. KG, Chichester.
A: I’ve sent your son a packet of seeds which are fresh. Sow them at the end of April indoors on a warm sunny windowsill and they will germinate in about six weeks. Don’t let the seed tray dry out but do not over-water.

Q: My daphne has been in the same pot for two years and looks very unwell but is very special to me. I have fed it with Maxicrop with sequestrine but it still looks sick. What would you suggest? I had another one and put it in a larger pot but it died. I don’t want this to happen again. DB, Portchester.

A: Thank you for the pictures. I see the daphne is half-buried in a larger pot. I would suggest you knock all the soil out of the large pot and replant it in John Innes No3 compost but add 20 per cent sharp sand to the compost and mix really well. Daphnes do not require lime free soil so JI3 is ideal. To encourage nice bushy growth, once the flowers fade nip out the tips of every branch and your plant will surprise you. Just in case other readers have problems with daphne, a 3ih layer of JI3 compost over the surface of the ground will transform the shrub, as does the pruning suggested.

Q: When is the best time to plant early potatoes? GL, Farlington.

A: They can be planted now if you live south of Portsdown Hill but at Easter if you live over the hill. Have several layers of fleece quickly at hand if frosts are forecast. Frost will damage the foliage and this will reduce the weight of the crop.

JOBS FOR THE WEEK AHEAD

• Buy runner bean seeds. These can be sown indoors at the end of the month if you would love beans in early July.

• Did you have a disaster sowing annuals for summer bedding? Don’t despair, there are lots of seedlings at garden centres and nurseries, already to be pricked out. Use insert cells, one seedling in each cell for perfect plants.

Choose F1 seedlings for best results.

• It is very upsetting to see millions of weed seedlings growing on the surface of soil dug over in the autumn and winter. These can be hoed off, but put a plank down on the ground if the soil is wet. Hoeing is best done when the soil surface is dry.

• Avoid cutting back hedges hard because birds are laying eggs. Think about feeding the birds and please give them some clean water to help them. Look forward to the rewarding birdsong every morning and evening.

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