you advise me when to spray autumn raspberries to avoid a small
worm that develops as the fruit enlarges? I was disappointed to
lose most of my crop this year. Also, when is the best time to prune
summer-flowering hebes? They have grown so much this season due
to excess moisture.
pests in raspberry fruits are probably the larvae of moths, butterflies,
beetle or flies, but without a sample it's impossible to tell exactly
which is causing the problem on your plants. There are, however,
precautions you can take to reduce the chances of it recurring next
year. In most cases the adult pest is likely to lay its eggs close
to the flower or developing fruit so that on hatching the grub can
bore into the fruit.
One of the most effective
ways to reduce damage is by applying an insecticide to the immature
fruit to prevent the larvae boring into the fruit. As soon as flowering
is finished and berries start forming, I'd try spraying every 14
days with Success Naturalyte or dusting regularly with Derris Dust.
Both are naturally derived insecticides and safe to use on fruit
during the early stages of their development. Follow the product
As for hebes, prune them
as soon as possible after they've finished flowering. It depends
on your local climate and the variety of hebe, but generally it's
best to avoid cutting them back in late autumn as that encourages
new growth during wet and humid winter weather ,which can lead to
It might pay to put
off pruning until early spring and then only give a light trim to
remove old flower heads. Don't cut back into old wood as, with some
varieties, it can fail to regrow, though you can remove the odd
whole branch if necessary to thin out a dense plant.
Gardener, Issue 171, 2005, Page 24
Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.