Q: The magnolia tree in my mother's garden has plenty of flowers but they are going brown and dying off before fully opening. I have also noticed the same problem in other gardens in Malpas and Caerleon.

Can you offer any reason for this happening ? MM, Newport

A: This is due to a frost we had two weeks ago as the flower buds were opening. Its just one of those things that happens from time to time. The same thing happened to the magnolia at the Secret Garden but it has recovered and putting on a good show.

Q: Last year I had club root on the cabbages. Can you recommend a way to solve the problem for this year please? RF, Cwmbran

A: Grow your cabbage and any other brassicas in a different place from now on. Club root once in the soil is impossible to eradicate so you will have to grow other plants on that patch from now on.

Q: I had a Japanese cherry blossom tree in my garden die after contracting the cherry blossom virus. Are there varieties of blossom tree resistant to the virus I can plant, or how long would I have to wait to plant another there if I dug the tree stump out? JG, Newport

A: As you have had problems with cherry blossom you could try something else and there is plenty to choose from. Crab apples put on a good show in the spring and the fruits are colourful in the autumn. Ornamental hawthorn is also very showy. Golden rain (laburnum) and lots of other flowering trees would suit.

Q: I try to keep the garden as tidy as I can, but I still get a plague of greenfly each year. Can you recommend a non chemical way of keeping greenfly off my roses? MA, Abergavenny

A: Mix some soapy water in a can and sprinkle over the roses every 10 days or so. This clogs up their breathing apparatus and they wont hang around for long.

Tip for the week:

Normally I don't start spraying roses until May but they are leafing up early so best start soon. Black spot, rust and mildew are the main problems and prevention is better than cure.

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