Gardeners’ queries

Press, 6 October 1989, Page 12

Gardeners’ queries

We have had a lot of wireworm in our potatoes for the first time this year despite keeping them well’ covered up. Could you advise whether there is anything that can be done to prevent them getting at our crop again this time round? M.C. (Chch).

Wireworms can do a lot of damage to the plants on which they feed, but do not appear to be a widespread problem. Control is not easy unless soil sterilisation is implemented, but this does not prevent subsequent reinfestation. It is important to be aware that the larvae occupy the soil for several years before they pupate. Trapping through the use of buried pieces of tuber or carrot which are lifted periodically and all the wireworms removed and exterminated is still one of the most used forms of reducing this pest. Crop rotation and cultivation can play a part towards restricting crop damage as well.

There is a considerable influx of the enclosed plant through much of the shrubbery of my garden. We don’t know what it is, and as it seems to be growing so rapidly we are concerned that it may take over if something is not done about it pretty soon. The other question is how to raise New Zealand spinach as it never seems to be available as plants, like silver beet and ordinary spinach, and what kind of conditions does it like? K.M. (Chch).

Honesty, Lunaria annua, seems to have proliferated in and into many gardens over the past months. Grown as an ornamental, it will grow quite steadily once it has become established and generally requires little or no attention. It is easily uprooted by hand and is not really considered . a problem at all. True, N.Z. spinach is not offered in plant packs, and although seed is availble in packets it may be necessary to hunt around for a stockist; alternatively, it may be

possible to procur some seed from another grower of it. Slow to germinate, the seed should be soaked in hot water for a few hours before sowing. A warm sunny position is ideal for best results and adequate moisture will assist in obtaining steady growth and a more palatable end product.

This yellow rhododendron seems to be growing quite well, but it never really comes into flower. It has been in the same position since it was bought two or three years ago, but although the flower buds form they tend to droop and turn brown without ever really opening. What can be done to improve it? ? (Chch)

The problem of the failure of the flower buds to open is considered to be a physiological one, possibly frost damage. Most of the smaller, yellow flowered rhododendrons have been found to be reliable and so it is suggested that, especially because of the recurrence of the trouble, resiting may solve the matter and could be done now.

We have a concrete bird bath which the water has taken the paint off. The birds (often several at a time) use it for both drinking and bathing then flying away to nearby trees. Maybe they need that cover when wet Could you also give us some advice? We have had to put cotton over so many things to keep the birds from damaging plants in the garden — for instance, silver beet is stripped, polyanthus and primroses have their buds eaten off. How do we stop all this? M.C. (Ashburton). Obviously when birds are attracted to a location they will pick and choose their food if there is a variety available. Again, it is noticeable that they will often feed voraciously on certain plants in some gardens or in particular areas, and yet not in others — silver beet and unripe blackcurrants immediately spring to

mind. -Netting, cotton thread, and various forms of bird scarers, both improvised and commercially available types, are the only harmless deferents that I can suggest to keep feathered feeders at bay. Gardeners’ Queries should be sent directly to Mr Mike Lusty, 56 Wayside Avenue, Christchurch 5. Samples should be separately wrapped in a plastic bag with air holes. Provide representative, good-sized samples, and your name and address. A nom-de-plume can be used for publication.