GARDENERS’ QUERIES

Press, Volume CXI, Issue 32636, 18 June 1971, Page 11

GARDENERS’ QUERIES

Could you please help me regarding a rhododendron? It bloomed the first year we had it, but in the three years since all the buds it sends up turn into' leaves. It has been given special rhododendron mixture along with others which have thrived and flowered beautifully, but not this one.—N. (Oamaru). It is not always easy to explain why a plant fails to flower although inspection of the subject on the site sometimes gives the answer straight away. Some plants often take time to. settle in after they have been lifted at the nursery, bad wrenching in the first place, too deep planting, too dense shade, insufficient moisture and too wet conditions can all be contributory factors. Sometimes problems right themselves given time. The specimen which you sent for inspection actually had a flower bud on it so there is hope yet. Flower buds of rhododendrons can be distinguished from leaf buds as they are rounder and plumper whereas the latter tend to be narrow and pointed.

trolling the growth. I think it appears to have had extra cuts since. We should like to ring bark our birch to prevent it becoming a giant and out of control. 1 understand it must not be

done too deeply. What tools would one user— Sylva (Christchurch). I have not had the time to investigate the tree in question but think that it may have been the one that was taken out completely. Complete ring bark is used to kill trees. Partial ringing and root pruning are practised on fruit trees to reduce vigour and induce fruiting but I am not aware that it will prove successful in preventing a tree from eventually attaining full height. A sharp, heavy knife will do the job.

I have just taken half a dozen seeds from my bird of paradise plant and wondered if a plant could be raised from these seeds or if the parent plant had to be divided?—Amateur (Nelson). Strelitzia, which is the generic name of the bird of paradise plant, can be grown from seed or division of the plant The seed, which is very hard, should be sown while fresh and soaked in warm water for a day beforehand to hasten germination. Could you please tell me whether passion fruits require pruning and if so, if it is very complicated, as we are thinking of buying one?—“Vine” (Timaru). Generally, unless passion fruits are pruned annually, they soon become a tangle

Please find enclosed a fungus-like growth found in damp areas on a lawn. The globular chain-like part erupts and enfolds from the accompanying sac, either by itself or on pressure. Puzzled (Christchurch). This is a fungus known as lattice, or basket, fungus. Years ago while visiting the gardens we noticed a young birch had been ring barked and were at that time unaware that this is

a method used for con- of old, young and dead

vines. The best time to prune them is in spring after the danger of heavy frosts has receded. Dead, diseased and weak growth should be removed first and then laterals can be cut back to two buds.

Old leaders should be replaced from time to time. If allowed to grow without such attention dr without some form of adequate training and spacing it becomes very difficult to manage them in later years. Enclosed Is a hoya leaf from a plant growing on a sun porch, though there is no direct sun on It because of blinds. The plant seems extremely healthy with hundreds of leaves on it although many have these whitish spots or blotches on them. Could you tell

me the cause? Also, it is growing in a large pot and it is seven years since I last repotted IL Could you please tell me what to feed it on or if it should be repotted In the spring?— F.L. (Rangiora). I would not repot nor feed as the present pot seems large enough and the plant seems healthy enough, judging from the leaf specimen. There is no evidence of any parasitic organism, being responsibly for the flecking displayed on the leaves, only the suggestion that the damage is mechanical or physiological. For instance it could be due to deposits from an aerosol fly spray or something similar. I have my garden sown down in lupins and they are now about 2 feet high. Is it advisable to get them covered in now or leave them until later on? I plant my garden early in September. Is it advisable to add super?—H.S. (Little River).

Ideally, the best time time to turn in a green crop occurs just when it is about to flower. However, this is not always possible, particularly where the ground is needed as it must be remembered that allowance has to be made for the rotting down of the crop: it takes about five weeks. You could leave your lupins for another month if they are not liable to get frosted; otherwise they could be dug in now. There is no need to add superphosphate now although your vegetables may benefit from it if. it is applied later on.