Gardeners' queries

Press, 20 November 1981, Page 10

Gardeners ' queries

Last year I bought a Vienna Charm rose bush. This did not grow and Was replaced by the nursery after sorting through many before finding a live one. My rose bloomed beautifully until towards the end of the season when fasciation appeared. This spring green buds were evident, but died off one by one. My mismanagement was blamed for the demise of the rose by the nursery. No other rose in the garden has succumbed. The nursery did not offer that particular rose for sale this year. What do you think? D.M. (Chch). J Vienna Charm can be a fairly vigorous grower, but the reverse is also true, and this particular rose is subject to disease. The cause of death of your plants cannot be explained without having seen them. Fasciation is as yet a not fully understood development which is known to occur in various trees and shrubs. Replanting of roses in the same site following the death of the previous one is not recommended unless the soil is either changed or it is sterilised. The parsley which I have grown in my vegetable garden was planted in autumn. It is nowlooking very sick in spite of regular picking and watering. Could you please advise what is wrong with it from the samples enclosed? T.M, (Chch). The poor condition of this parsley is due to a very heavy iniestation of aphids which have been breeding on the plant. Prevailing conditions have been conducive to the prevalency of this pest. The

debility caused to the parsley is such that it would be advisable to cut it hard back to stimulate fresh growth. The foliage removed should be burned and the plant sprayed with maldison. Would you please comment on the enclosed leaves from a five-year-old Wheeny grapefruit tree? It is growing by the corner of the house, close to the path. It is sprayed occasionally but does not get any other specific attention apart from some chicken manure from time to time. What should be done to improve the. appearance of the leaves, and more juice and size in the fruit? K.H. (Chch). The leaves do not really indicate any problems, the crinkled or bullate appearance being regarded as a physiological characteristic of this particular variety, generally thought to be induced by cold conditions. Exposure to wind is considered particularly likely to cause this condition. Citrus very definitely need shelter if they are to thrive and no amount of other attention will counteract the detrimental effects of exposure to wind. Good drainage, but a moisture retentive and fertile soil will assist in obtaining good crops. Spraying for scale insects and leaf roller caterpillar generally becomes necessary at some time or another, while annual feeding is also beneficial. Fertiliser is best given in two applications, one third in August, and the balance in early December. The amount of fertiliser to give is roughly o.skg for every year of the tree's

age to a maximum of 3.5 kg for a mature one. I have a border which is edged by these little daisy plants. They have done well until recently when it was noticeable that they were beginning to look sick. What is wrong with them? “Disappointed" (Chch). The very free-flowering and attractive perennial daisy is unfortunately susceptible to rust, the infection which is causing the debility in these plants. Suggested treatment is to spray them with triforine as soon as is possible and to repeat the application within a fortnight. I enclose the sections of several stems from my hydrangeas which have a type of mould or fungus on them. Many of the growths on these plants are also almost white with this covering and some of the plants are beginning to look not-so-good. What is iit, and what is the cure? "Quick-cure” (Kaiapoi). The problem is not one of disease but the severe infestation of the plants by the hydrangea scale. Control at this time of the year is usually difficult, and it is best to wait until early summer. The plants should be sprayed with white oil or summer oil at a strength of 1:40. A thorough coverage, particularly of the under sides of the leaves, is essential. Do not spray in very bright sunshine or in hot weather as the plants can suffer damage as a result. A repeat spray may be warranted. In winter, apply lime sulphur or spraying oil to point of run off.