Gardeners’ queries

Press, 24 January 1986, Page 14

Gardeners’ queries

GARDENING

by

M.Lusty

We have a very large specimen of ceanothus. Every year part of the plant is affected by something which makes the leaves turn yellow and then brown until they drop off. The branch affected then dies. Could you advise of the cause, and if it can be treated? R.B. (Cheviot).

As there are a number of diseases which can cause similar symptoms to those described it is not possible to make any definite comments without seeing fully representative samples. Heavy infestation by scales, age, and split branches, have been noted as also contributing to die back in these trees.

Our sweet peas have been a complete failure this year. -Poor germinatio and subsequently dying plants were common to three separate sowings. The few plants which did survive have grown to about seven feet, and until recently all the flower buds have been blind. Our glasshouse, built of a type of plastic Instead of glass, is not really suitably sited, getting only a few hours sun in the middle of the day. The tomato plants are spindly and slow to develop fruit trusses. Would an electric light help matters? Our lawns and flower beds are over-run with a distinctive, yellow-flowered creeping plant which I am told is oxalis. Is there any cure? L.K. (Waimate).

Sweet pea seed is very much prone to soil-borne fungal infection, and dampingoff disease. These problems can be minimised by sowing in different places each year, ensuring that the drainage is adequate, dusting the seed with a suitable fungicide such as thiram or germaid, and

not over watering. Excessive use of nitrogenous fertiliser and lack of light are detrimental to flowering. Appropriate plastic is a suitable and widely used alternative to glass. Electric light could be used successfully in place of natural light. There are several plants which could fit the description of the plant mentioned so it would have to be seen to be identified.

Can you help me with these two questions? 1. How and when do you propagate Gypsophila “Bristol Fairy”? 2. Is it suitable to use shredded newspaper and cardboard in the compost heap? If so, what percentage can be used without the chemicals spoiling the compost? N.H. (Christchurch). Gypsophila ‘‘Bristol Fairy” can be raised from seed at almost any time other than in mid-winter and the heat of summer. Propagation is achieved by means of 50 to 70 mm long basal cuttings taken in spring, or by grafting similar length shoots taken from unfldwered, previous season’s growth on to pieces of root also in spring. Regarding the use of shredded paper in the compost heap, much depends on the type of other organic matter which is incorporated in it Whatever is used, the paper should be well mixed with the other material, and not placed in thick layers. There is no problem from the printing inks causing contamination.

I have two Aloe vera plants which have propagated themselves in the last few months. I have transplanted most of them when about one inch high. Could you give me some information on how often they

should be propagated, whether they have to be kept together, and whether the young plants will be natural propagators like the parent plant? L.K. (Ranglora). Aloes can be raised successfully from offsets when they appear. There has been no particularly noticeable differences between potting

up such plant straight away, and first drying them. Offsets will in time reproduce in the same way as the parent plant. Plants can also be raised from seed. Gardeners* Queries should be sent directly to Mr Mike Lusty, 56 Wayside Avenue, Christchurch 5. Samples should be wrapped in a plastic bag with air holes. Provide representative, goodsized samples, and your name and address. A nom-de-plume can be used for publication.