winter we chopped back our pittosporums. The new leaves seem crinkled
and have tiny yellowish round lumps on them. Should I spray?
yellow lumps are sap-sucking psyllids. You could spray if the plants
are severely affected but most pittosporums grow reasonably well
even with a sizeable population. Rather than spray, I recommend
you fertilise and water in dry periods to encourage lots of strong
Psyllids prefer to feed
on the new shoots so once the growth is long enough a regular trim
with hedgeclippers is usually sufficient to keep the psyllid population
at relatively low levels. The problem is usually worse in the heat
of summer and can almost disappear with the onset of cool moist
autumn and winter conditions.
If you do spray, a general
insecticide such as Rogor 100, Confidor or Mavrik should give good
Gardener, Issue 139, 2004, Page 27
Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.