do you get rid of whitefly? We seem to get it on everything in the
summer. I spray with neem oil, but that only shifts it from one
plant to the other.
can be tricky to control, especially in warm weather when they breed
rapidly. Adult whiteflies can simply fly away to avoid being hit
with contact action sprays. And in the height of summer, even if
you manage to knock down the adults with a contact spray, you need
to spray again around five days later to get the next generation
that develops from the scale-like nymphs on the leaf undersides.
Keep your garden as weed-free
as possible, especially from sow thistle (puha), which whitefly
love. Regularly check plants that you know are susceptible.
As soon as you spot a
few adults, spray - don't wait until mid-summer when there's a population
explosion. Ideally, use a systemic spray such as Target, Confidor
or Rogor which not only knocks down adults but travels through the
leaf to get to the nymphs below. Spray three times at five to seven
day intervals and take note of the withholding period on the label
before eating any sprayed vegetables or fruit.
If you want to use organic
sprays such as Nature's Way Insect Spray or neem, make sure to get
good spray coverage on the undersides of the leaves to get the nymphs
as well as above for the adults. Spray in the cool temperature of
early morning or evening when the adult whiteflies are least active.
Then, for the rest of the season, keep a careful watch for reinfestation
and repeat the three sprays again if and when necessary.
Gardener, Issue 156, 2004, Page 28
Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.