Slugs and Snails
White Cabbage Butterflies
We all know the feeling: You plant brassicas and your old friend Pieris rapae, or White Cabbage Butterfly crashes the party and want’s to eat all the snacks! Accidentally introduced to New Zealand in the summer of 1929-1930. Like most of us the adults love summer and are active between September through to April.
The female butterflies lay their eggs on the underside of leaves, these are small and though white when freshly laid will turn yellow. The good news is that they can be wiped off easily with a damp cloth. (It’s time consuming but fairly easily done).
The caterpillars once hatched will eat their egg casing and then set to work on your plant. They like to get to the heart of the matter, and your plants! And as the plant grows they will burrow in.
They are territorial, they do not like shaded areas, and they do not lay eggs when it is overcast or raining.
So what can we do about these bugs?
The best solution by far is netting. It is less than $5 a metre for 2 metre wide netting. Another option is to use net curtains (keep an eye out on the SPCA or Hospice Shop). Cover those plants as soon as possible to avoid the butterflies getting to your plants. You will still need to keep an eye on them though – the sneaky buggers will constantly be trying to find a way through your defences! As it is believed that the butterflies are territorial – fake butterflies can act as a deterrent. They also look kind of neat in my opinion. Whilst not as effective as the all encompassing netting, they do seem to deter the butterflies – they will still fly around, but do not seem to want to land on your plants.
Planting Nasturtiums will distract the butterflies away from your crops.
I have also heard (NOT TESTED THIS) that egg shells around the base of your plants will deter them (in the same way faux butterflies do) – however it needs to be quite a thick layer of shells.
If you want a bit more revenge, and exercise – a badminton racquet will certainly make gardening a little more interesting!
A visual check under your leaves every now and then to pick off any caterpillars lurking there will put down any damage caused by those who break through your defences.
Now just to make your day: In 2010 Pieris brassicae, Great White Cabbage Butterfly (Yip, it’s just like the White Cabbage Butterfly – but bigger) was found in New Zealand. It is larger (55-70mm wingspan), can fly great distances, and unlike it’s lesser cousin the caterpillars are yellow and black.
Killing your plants with kindness
I’ve had this explained to me as ‘teenage boy syndrome’ – the plant stalks are growing too fast for the rest of the plant to keep up with.
The result is a lot of stalk and small, deformed leaves.
This is caused by excess nitrogen.
Solution: Do not overfeed your plants.
Felis Catus Spazicus
There is no cure 😆