Gardeners’ Queries...

Press, Volume C, Issue 29517, 19 May 1961, Page 7

Gardeners’ Queries...

I have a Cotoneaster watereri about eight years old. It grows well, and has produced ample Hower, but so far no fruit has set. What is wrong. Would a Kalmia latiteUa be “shiftable”? It is not doing too well where it is—the young leaves get brown tips. Can anything be done to give Proteas more colour? They flourish as far as growth goes.—(A.B., Cashmere.) Cotoneaster watereri is not bisexual, so that the production of flowers should lead to the formation of fruit, even on an isolated plant. Pollination is also normally satisfactory, with the insects about at that season. It is possibly due to the attack of the fungus Sclerotinia. but I cannot be sure without seeing specimens. Could you send me fruitlets just after flowering and before they drop? Kalmia latifolia will Shift quite well—they form quite a compact root ball. Give a good water before you shift. The job can be done any time now. When Proteas are pale it is usually due to the variations which arise from seedling raised plants. Some come dark and others light. Unless the plants you buy have been raised from cuttings—which are usually shallower rooting—you cannot be sure that the colour will be of the desirable darker shades. I know of no recipe for inducing darker flower colours in plants which are naturally pale. The leaves of my chrysanthemums have browned and died back almost to the flowers, and those remaining are unhealthy in appearance. They have been sprayed thoroughly, but probably not soon enough, with lime sulphur. Can I use cuttings from them if I treat the plants and soil with a suitable spray? Most of them are good and new plants. f’Advice Wanted,” Sydenham.) It is impossible to answer this question without specimens to examine. The production of brown leaves could be the result of a number of causes, the treatment being distinct in each case. One of the commonest causes is chrysanthemum eelworm, which can be serious, particularly if plants have been grown on the same piece of ground for a number of years. The best means of combating this pest is by the use of one of the organic-phosphorous sprays, such as parathion, on the plants from the cutting stage onwards, together with the use of a fresh piece of land for growing which has not carried chrysanthemums before. However, parathion is very poisonous material, and not normally available to the home gardener. Please send me specimens of plants to verify the treatment. Plant for identification. (Mrs S. F. Bailey, Waimate.) Your plant is Alstroemeria pulchella. This plant is not too common, and is quite distinct from the ordinary alstroemeria which has orange flowers, in the unusual combination of red. green and purple all in the same flower. Strictly speaking, the plant is not a bulb, but has fleshy roots, which can be invasive if it likes the place it is growing in. 1 have been troubled this season with eelworm in a number of chrysanthemum plants and I would he pleased to know if B.H.C. would be effective against this pest. If not. what would you recommend other than parathion? (Barrington St., Christchurch.) I am afraid that B.H.C. Is not effective against chrysanthemum eelworm. Parathion is the best control, although it is not recommended for the home gardener. If your soil is infected by the repeated growing of infected crops it would be best to abandon this site in favour of a clean spot. The soil can be cleaned up by Methyl bromide fumigation, but this also is not a job for the home gardener. If the soil is clean, however, you can clean up infected stock plants by the process of “hot water treatment,” and so keep it clean. This process Involves the use of a thermostatically controlled water-bath. At the end of the season, when the stools are lifted for storing, they are dipped in the water-bath for five minutes with the water temperature at exactly 115 degrees Fahrenheit. This temperature must be exact—if it is too high the plants will be harmed, and if it is too low. then the eelworms will not be eliminated. It is a rather laborious process but is the only method. besides parathion sprays, for cleaning up your stock. How ean I grow a walnut tree? Is it possible to grow one from the nut itself, or does It have to be grafted? (W. H. R, McG„ via Collingwood.) Walnuts are raised by nurserymen using both methods, seed raising and grafting. Seed raised plants are liable to vary slightly in their characters—some may have small fruit and others large, or some may have thin shells and others thick. However. I don’t think this is of fundamental importance, and anyway grafting is a very tricky process with which even the nurseryman doesn't always succeed. Gather seeds (nuts) now. clean off the husk—the fleshy outside layer—and sow the nuts straight away about two inches deep. Don’t let the nuts get dry, as you buy them for eating, or the percentage Sermination is much reuced. Young plants are not quick in growth to start off. but grow fairly rapidly when three or four years old. From a sowing now you will get germination next spring, but don't move the seedlings before next winter. We put In nearly 1-acre of mustard seed, and the birds had a merry time! What they didn’t eat as seeds they pulled out as shoots. Any suggestions on treatment, please. I’ve tried all the string, tin can and regular methods, and biack cotton is too big a proposition for a large area. Also, what is a sure killed tor twitch? ("Gardener," Hokitika.) Bird damage is not easy to control effectively—even the commercial "bangers" seem to lose their effectiveness after a while I would suggest coating the seeds with red lead before you sow. About one part to 10 parts of seed. Add a little kerosene to the mixture as it is being stirred together—this will stick the red lead to the seeds more thoroughly and also avoid your appearing like a Red Indian after a brisk period of sowing! Also make sure the seeds are adequately covered—the farmer’s method of rolling would not go amiss in avoiding bird damage. Twitch is effectively controlled with Dalapon, applied at I to jib per 10W square feet. This material has to be absorbed by the foliage to act. and is most effective when plants are growing rapidly Even then it may take several weeks to show its effect, so don’t be too eager to see results. A second application may be required, which is usually adequate for complete control.

I planted a box of Lilium auratum last month, and every one eame up. Seedlings are now about an Inch tall and I am wondering how to earry them over the winter. How long do they take to flower? Two disappointments in my gaarden are the Chinese lantern plant, Physalis, and Herberts wilsonae. both of which flower but do not fruit. Can you help? (C.E.W., St. Albans.) Thank you for your thorough letter. Lily seedlings are usually quite hardy, so you should have no difficulty in overwintering them. Many people sow direct in open-ground beds. Placed in an open, sunny place they should be quite safe. They will take three or four years to flower I'm afraid this is the first time I have heard of failures to fruit with the two plants you mention—l have regarded them previously as very reliable. Also, I am unable to find any explanation in the books. A lighter soil would perhaps be a help.

Can yon trare the cause of hollow cam la my cotrot.? There are some smallish Insects Inside but I don’t know wbethor they are the cause. The varioty was "Topwelght,” sown on October 8, on lightish soil which has had poultry house cleanings dug tn. (J.8.H., Temuka.) The cause of your carrot "hollow core” lies in the growth of the plant rather than in attack by pest or disease. The wet summer, combined with a light soil, ample fertiliser, and a strong growing variety, have all combined to produce vigorous growth in which the core has not kept pace with the outer layers, giving rise to the internal cavity. The presence of a few millipedes and other insects is purely incidental, since these are characteristic insects feeding in such secluded and sheltered cavities. Potato is another vegetable which is liable to develop fa the same way in similar circumstances.