Gardeners’ Queries

Press, Volume CVI, Issue 31321, 17 March 1967, Page 6

Gardeners’ Queries

We have had a very good crop of potatoes this year which outwardly look very healthy. However, many of them when cut open show discoloration and do not seem Fit for eating. They have not been sprayed at any time during the year nor has any special attention been given them. What is the cause and how can we prevent a recurrence next year?—S.F. (Christchurch) The disease ia regarded as physiological and little is known about it at present. It is called internal brown fleck or brown spot and causes brown spots or flecking throughout the flesh of the tuber. Suggested causes include lack of sufficient moisture during the later stages of growth, extreme soil acidity and varietal susceptibility where these are generally high yielding and grown on rich soil. This year many of our azaleas have developed peculiar growths on them. What is to be done about it as we would not like to lose them?—R.A. (Christchurch) The symptoms are those of leaf gall caused by the fungus exobasidium sp„ which

emerges in spring giving the leaves a very enlarged, crinkled appearance not unlike leaf curl of stone fruit. What happens is that the fungus grows between the layers which make up the leaf and eventually bursts out on the leaf surface, where the spores become liberated by air currents. A whitish grey and finally black coating later makes the disease even more prominent, but this is due to the presence of a secondary fungus which is parasitic on the exobasidium. It is usually sufficient to cut out the infected portion with a short length of healthy wood attached and burn them. Spraying with Bordeaux mixture at the rate of 3:1:50 at or near the end of flowering and continuing at fortnightly intervals until just before Christmas will control infection where it has been or is severe. It Is not a really serious disease and a similar one can affect camellias. I wish to lift my gladioli but am told various ways of doing this so am not auro what best to do. Could you please tell how and when to lift and replant these flowers as I would like to do it correctly?—S.F. (Sumner) The article on this page today should give you sufficient information. Enclosed Is a specimen of Lily which I have grown from seed. Could you please tell me its name?—"Christchurch." Specimen would almost certainly appear to be that of Lilium longiflorum or one of its many forms.