TO CORRESPONDENTS.

Auckland Star, Volume LXI, Issue 27, 1 February 1930, Page 6 (Supplement)

TO CORRESPONDENTS.

Correspondents will greatly oblige by observing: the following rules In sending questions for publication In these columns:— I—Letters should be lp not later than Tuesday to be answered the same week—addressed to Garden Editor, "Star" Ofllce, Auckland. 2—AVrlte on one side of the paper, ana make all communications as concise as possible. —Flowers, etc., sent Tor naming 1 , must be sent separately, and, If possible, packed in a tin or wooden box—cardboard boxes are very liable to be broken In transit and the contents damag-ed. 4—The full name and address of the sender must always be sent, but a nom de plume or initial may be given for publication.

KELVIN (Remucra) ?asks : (1) Would it.fbe harmful to a ■ flowering gum If • tlic brunches were trirumed after It had linished flowering, and seeds removed? (2) Th#- latest month that celery can be moved.-jstl). No. The trimming should be done rs soon as the flowers are over, (-!) Celery could be planted out as late as the end of March, but it would not make very large heads. For a fair crop the end of January or beginning ol February is quite late enough. QUERY (Ohaupo) sends a sweet pea flower l'or inspection. (1) Are the little insects at all injurious, ahd are they the same as those that eat the mushrooms in warm weather? (2) Is sulphate ol ammonia a good fertiliser for the fiowei garden? (3) What manure will give hydrangeas a pink shade?—(l) The "insects are thrijy. They are often found on sweet pea and other blooms in the summer time. They are also fourid on mushrooms. Spraying with nicotine will keep them down. (2) Sulphate oi ammonia is all right as a manure foi flowers if used in small lots. It sup- | . plies nitrogen, antl that tends to make foliage, You would need to apply some phosphates, such as superphosphate, bonedust or slag as well. (3) You can turn pink hydrangeas blue by applying iron or alum. The pink, however, is the natural colour, and .if your hydrangeas are blue it is probably due to your soil, and if so, short of new soil, it would be difficult to alter. PLUM (Devonport) sends a leaf of a plum tior identification.;— The trouble is due to t plum rust. .To control the disease it i is-necessary, ns soon as the leaves have fallen, to collect and bury them. All - soil around the, tree should be dug over. I As the disease attacks all stone fruits i- the. same method of control is necessary with / them. Spraying should be done i' as oon as the buds -begin to move in '/ the spring, using lime sulphur, I—lo, and again when the fruit has been picked, which will be about this time of the year, using lime-sulphur, 1—420. R.G. (Devonport) writes: (1) Seveiral of mj tomatoes have been attacked by a diseasi which , turns the stems brown. Will this affect the fruit, and does it spread? Hov can it be prevented? (ij).lf saltpetre hai been kept in a dry ijlace for two years wil 4 lt be good? Can it be used in place o< nitrate of soda?—(1) There is a diseas< which attacks tomatoes, turning the stems .. black and causing the death of the plant If tile stems of your plants are only dis coloured, without any apparent effects on the plant, leaves, or. fruit,,it is all right, and may not be a disease. Black stem rot ■' is a bad disease and cannot be cured b.v spraying. Pull up the plants burn the whole lot. It is a disease that is transmitted by the seed. (2) Saltpetre will be all right, kept dry. It can be used in a similar manner to nitrate of soda,- but is a better fertiliser, as it supplies both nitrogen and potash. REMUERA writes:—Can you give me any information regarding ah insect which lias got into my liouse. It forms a white fluffy ball-like substance. It comes out of cracks and is very quick?—l think it must be silverflsh, a small silvery coloured insect. Napthalene, or moth balls; as tney are called, placed about th • shelves, etc., will get rid of them.

GREY LYNN sends a few blackberries for identification. They are growing on a section, and don't spread, and with support will grow ten feet high. The old wood dies back each year and tlie fruit is carried on the new wood.—There is no doubt tliat they are a variety of blackberry, and apparently are rather more civil than most and are satisfied to stay in one place. I could not give them any particular name. There are several varieties of blackberries, andhybrid blackberries are grown in Europe and America. It may be someone has imported one or these varieties. INVERAY (Birkenhead) whites: I have an orange tree six years old, growing in a , sheltered spot. It looks healthy, blooms well, but sets no fruit. There is a black coloured smudge underneath the leaves. Can you advise?— The black smudge is due to scale. Use red oil spray. Why the tree does not set fruit I cannot, say for certain, In many cases an application of potash and two or three light applications of nitrate of soda will induce fruiting. HORTUS (Mount Eden) writes: (1) What is the cause of the disease on the silver beet leaf? (2) Also on .the geranium leaf, and what spray will eradicate them? (3) What spray will keep aphides off young cabbage plants? (4) Tiny black insects appear on the leaves of an orange, causing them to crinkle. What spray will kill them?—(l) Rust. (2) Rust. Bordeaux mixture applied during the early spring or as sooo as the young leaves appear, Both beet and geranium rust are difficult to control, and as they are usually considered not worth troubling about the diseases are allowed to run their course, and the result is that they appear year after year. Clearing away and burning all diseased foliage, so as to prevent the carry over spores from finding lodgment in the soil is one of the m6aus of control. Spraying should be done early, as the disease can be anticipated, having appeared once. (3) Cabbage aphides are very difficult of control, especially in summer. Warm soapy water at about blood heat, used as a spray, will, kill . the insect. Nicotine will also kill tKem. The difficulty in dealing with the cabbage aphis is that the formation of the leaves and heart of the cabbage gives much protection from external application. (4) This is a black aphis. Spraying with nicotlno will control it J.H. (Mount Albert) sends a leaf of an aspidistra and wishes to know what is the matter with it. The plants are watered carefully and occasionally receive a little nitrate of soda. What- is the cause of moisture appearing at the tip of young leaves and shoots. This moisture only appears in the morning, and, of course, dries off during the day.—There are some scale insects on the leaf. A sponging with some soapy water will clean them off. The moisture that appears on the tip of the leaves is due to the moisture exuded by the leaf during the night not evaporating,' but, due to cold, moist *air, it condenses and forms drops of water at the tip of the leaf. This process is general, but outside or in-greenhouses, owing to moist air, it is not so noticeable as in the drier air of a living room. M.B. (Remuera) sends a specimen for identification.—lt is Parax Sinclairl.