Readers' problems solved.
Q: A friend at Drayton has a laurel hedge which has been reduced considerably. Most of the it has responded by sending out plenty of new shoots. Just one has yellow leaves and the veins are very pronounced while all other parts are yellow.
A: This phenomena is known as chlorosis and is down to a lack of magnesium and nitrogen. All the shrubs are taking these elements out of the soil. There is a method of overcoming the problem. Use just a teaspoon of Epsom salts and a tablespoon of sulphate of ammonia in two gallons of water and apply very slowly to the roots. Do this at any time during May. The entire hedge would benefit from using fish blood and bone fertiliser using only two ounces per yard run directly before rain is forecast.
Q: I read your advice about growing my own mushrooms and have put the mushroom compost into a suitable box in my shed. The instructions tell me to top dress the compost with loam. Can I use garden soil? VC, Cosham.
A: No. If you do weeds will grow. Buy a small bag of sterilised loam from your garden centre.
Q: I keep a lot of your articles in a scrapbook and read them during horrible weather. Very often you advise using cosmea to fill gaps in the garden. In pots at the garden centre they are expensive but wonderful plants. Can you sow them from seeds? SL, Petersfield.
A: Yes, more than 100 seeds for £2 and they are sown right now either indoors or in pinches straight into the ground. Do this on a pleasant day.
Q: My compost bin contents look like a liquid mess because the lid blew away. How can I get rid of the compost? DS, Cowplain.
A: It won’t be wasted, dig it into any place in the garden or in the bottom of a trench where you are planning growing runner beans.
Q: I was cleaning out the shed and found a large bag of sulphate of potash which is dry but in a solid block. Can I use it and any ideas on how to break it up? WK, Rowlands Castle.
A: Yes, it will be perfectly OK if you break it up into dust again. Use dry strong material to cover the lump and gently break it up with a hammer. Take your time because once you start it will become easier to do. Potash is good for flowers but only use an ounce per square yard, never more.
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