Gardeners' Queries

Press, Volume CII, Issue 30211, 16 August 1963, Page 6

Gardeners' Queries

The outside leaves of my polyanthus become discoloured and gradually die (specimen enclosed). There are signs that some of the leaves have been chewed by some insect but I think that this is incidental. Could you explain the cause and suggest a cure?—“Fendalton North."

It is not uncommon for the older leaves of polyanthus to die away during the winter. This is nothing to worry about as the central portion will produce new growth in the spring. Around your clump were noticeable signs of fertiliser. I wonder if. when you applied this, some fell on the leaves, for this would be likely to cause the leaves to die. As you say, there are signs of damage by an insect; this is one of the leaf rollers and can be controlled by an application of D.D.T. or lindane.

I live In strong limestone country and I am hoping for guidance for this type of soil. Should lime be applied at all? Should organic matter be applied more frequently? I am trying to grow a blue hydrangea and I have applied flowers of sulphur and rusty nails, but the bush still has the appearance, which your recent article on lime now tells me is iron deficiency. There is also an azalea in the garden which I have kept alive for many years, but it has never flowered. Can you offer me any advice on these problems?—“Amateur” (Tawaho).

Lime should be unnecessary on your soil and there should be no need to apply organic matter more frequently than you would on any other soil. Continue to apply your flowers of sulphur around your hydrangea and also apply alum at the rate of lib to 21b according to the size of the plant. Apply a mulch of some acid material such as peat. The foliage should be sprayed at monthly intervals with ferrous sulphate at the rate of Hioz to a gallon of water to which a few drops of spreader has been added. Lift the azalea and shake off all the loose soil. Dig the hole to take the ball rather larger and deeper than the ball of the plant. Make a mixture of two parts of peat and one of sharp sand and place some of the mixture in the hole so that the top of the ball of the plant will be level with the soil surface, and then fill in the hole around the ball with the mixture. Top-dress annually with peat. Even better results will be achieved if you were to construct a raised bed

above ground level and fill with a mixture of equal parts of acid soil sand and peat, and plant in this. Whenever watering is necessary use only rain water.

Can you inform me of the best method of controlling moss from my lawns? It Is becoming increasingly more prevalent. “Moss” (Sumner).

Moss is usually associated with damp conditions. bad drainage and heavy shade. Improvement of drainage will help and selection of a grass that will tolerate shade will lessen your problem. Lawn sand in the form of spot treatment at the rate of one ounce to the square yard A mixture of sulphate of ammonia, sulphate of iron and sand in the ratio of 6:1:1 makes up a suitable lawn sand. In view of the prevalence of moss on your lawns use a sodium pentachlorophenate moss killer, which is available under a number of proprietary names; use according to the maker's instructions. Once the moss has been killed the area should be well raked over, top-dressed with fresh soil, and resown with grass seed. Unless the conditions responsible for the moss are rectified, it will continue to appear and cause trouble.