GARDENERS’ QUERIES

Press, Volume CVIII, Issue 31658, 19 April 1968, Page 6

GARDENERS’ QUERIES

Enclosed Is a sample of a geranium “gone wrong.” What is causing the disease and is there a remedy? Will the trouble spread to neighbouring plants, be they geraniums or other kinds? It 1* limestone country here, the plants are growing against the house the roof of whieh ha* a good overhang. Blopd and bone is used and sometime* a little bonedust There is little water available for the Srden. "North Canter* iry.”

' Aphides snd white fly covered the leaves. Although it is almost time to cut them hack you could still spray with malathion and repeat in about one week's time. Aphides will attack many plants although not all species feed bh the same kind of plant. Geraniums will grow well in * hot, dry position and do pot need much moisture provided . the soil contains some organic matter. They de best in a near neutral soil, responding neither to acidic nor alkaline Conditions. Contrary to some opinions a sunny position is most desirable for both foliage and development of free flowering which Is inhibited in them by shade. Excessive feeding with fertilisers should also be avoided but again the widely-held belief that they do not need anything at ail to do well is erroneous.

We have just bought a section with a new house on it As yet there is nothing on it with the exception of Shed, fences and driveway. We are shortly putting down a lawn, but not being gardeners are not too keen to start planting things without advice. Can yon give u* a list of what we eould grow, together with advice where to put them?— “Amateur” (Christchurch).

Frankly, this Is the sort of query thst Is just not possible to answer properly through correspondence at there are too many factors involved and points to take into consideration. Your own objectives are of primary importance as tills will decide how much area you wish to allot to different aspects of gardening: vegetable plot, lawn,

whether you want flower beds and/or roses, etc. If you have a small section you will be well advised not to plant tall or very rampant plants. Books, catalogues, plant stockists and/or one of the local landscaping service* will give you sufficient ideas to formulate a planting scheme. Our pears, Packham* Triumph, have this year produced a lot of odd shaped pears a* yon will see from the two samples sent you. The tree Is not very old and till now has always had ordinary looking fruit on it. We spray in winter and spring and just before Christmas and the tree looks healthy, to us. Can you say what is wrong with It?—BJ. (Christchurch). The fruit has a virus infection known as stony pit which is, incurable. The only way in .whieh it is spresd is by budding or grafting. Its preponderance is variable from season to season and internal pitting can sometimes be very severe. It may be advisable to pull out the tree now before it get* too big and replace it with another one. Could yon please advise If it is possible to graft a bud on to an orange tree. I have a well-established Carters Navel and am anxious to obtain an old established sweet variety which a friend of mine grows. Would you please advise the best method of obtaining this as I have had considerable success with whip-grafting apples. —“lnterested” (Akaroa). Grafting or budding of citrus should not present any problems and the same techniques apply as with any other plant grafting. The enclosed weed appeared on my lawn within the last few months. It is spreading fairly quickly, encroach-

Ing on the garden almost overnight. Could you advise the name of weed and eradication treatment required. —AJI. (Christchurch?oi 12345 23454 The weed is Dichondra repens which is or can be used to form a most effective weed lawn- It is a native and may need repeated treatment for control. In fine lawns use MCPA plus MCPP, otherwise 24D. It will be advisable to wait until spring before applying it. The eneloeed sample is from a Cupressus lepto* clade tree. Would you please tell me why the foliage has changed from green to rusty brown. The inner foliage is still green. The tree was bought six months ago* “Evergreen” (Christchurch). This is an attractive little conifer which grows about 10 feet tall with blue green foliage and pyramidal habit. It Is listed under a variety of names Including Cupressus thyoldes leptoclada, Retlnispora leptoclada and Chamaecyparis thyoides andelyensls. It appears to be suffering from cypress canker which is not readily cured although Bordeaux mixture applied in autump and again in spring ean help.

I would he grateful if you could outline the procedure, etc., for a home garden strawberry , plot using black polythene in the manner of commercial growers. Advice on spraying also would be appreciated.—R.L. (Rangiora). Commercial practice in: planting out of strawberries tends to vary-from area to area and even from grower to grower. Very ciooely planted single and alternate double rows to widespread double ones are generally used In intensive practice, which is not necessary in the garden where

problems such as labour, etc., do not arise. Black polythene sheet, 3 feet wide of .001 thickness, should be used. This is. laid over deeply worked friable soil as free of lumps a* possible and which has been well watered in advance It should be ridged and consolidated to about 6 inches high and flat topped. A complete fertiliser should then be applied to the top of the ridge which can be raked in before the polythene is laid out. The latter should be kept taut and about 6 inches on either side covered with soil. A marking board with projecting nails at desired spacings or a bluntended flat piece of steel fashioned for the purpose are the most usual forms of puncturing tiie polythene. The latter is used for dibbing the plants into the soil as well. A simple spray programme which could be initiated require* Bordeaux mixture and summer oil tn late August or early September for leaf spot and mite control followed by captan or tiiiram before flowering and repeated thereafter about fortnightly intervals for botrytis control. Prevalency of other pests such as mite, and prevailing weather conditions conducive to botrytis infection may necessitate additional coverage. This, briefly, outline* the salient points of strawberry growing under polythene. I would be grateful If you eould advise me what is the cause of the damage to the rhododendron leaves enclosed and the treatment Also eould you Identify the berries. Are they edible?— E.C. (Christchurch). The damage on the rhododendron* is physiological and is possibly wind burn and/or sun scald, often accentuated if the leaves are moist It is very prevalent and there is nothing that can be done about it The berries come from the North American plant Phytolacca americana. Eating them la not recommended.