Very Hungry Caterpillars

[doversoul1]

My Savoy and red cabbages and all other cabbage family have been eaten to thread by caterpillars. I know kales and purple sprouting will recover but the site is quite appalling. I have been accused of feeding the birds too well. Well, that might be the case but have other gardeners on the Forum similar problem?

Badgers in spring and now caterpillars. It does make one wonder if it’s all worth it (I know the answer though).

[ardcarp]

Are you organic, Dovers? Sprinkling stuff out of tins springs to mind. We don't do brassicas as we're away for big chunks of time and not able to husband then. In general it's been a much better year for moths and butterflies (last year was disastrous) so it's an ill wind, etc, etc

[umslopogaas]

I dont grow brassicas because of the caterpillar problem. I did once try netting them, but the butterflies seem to be able to drop their eggs through the nets. Maybe raising the nets further away from the plants would help.

The options for chemical control are ... well, for amateur gardeners there arent really any. Organic soaps and the like that work by contact action are OK, but you have to get contact and the little so and sos hide deep in the heart of the plant. Also these products wash off in the rain. Systemic chemicals containing (eg) acetamiprid (available in your local Homebase, but I'd better not advertise the product name) would work, but are not approved for use on edible crops. I cannot of course recommend using a pesticide for an unapproved purpose, because that would be illegal. Based on experience of other pesticides and crops, I am confident that a withholding period of a month (ie, last spray a month before harvest) would be sufficient to allow the level of pesticide in the plant to decline to negligible levels. The stuff is in any case pretty harmless, or the government wouldnt allow it to be sold to amateur gardeners.

The RHS veg book suggests spraying with products containing rotenone, pyrethrum or bifenthrin, but that was in the 2008 edition: I dont think bifenthrin is available to amateurs any more. The other two may be, but again, check the label for approvals. Rotenone is the active ingredient in derris; it is highly toxic to fish. The original pyrethrum is derived from the plant, but there are many synthetic variants.

Since the caterpillars are active at night, the RHS also suggests hunting them by torchlight. This may appeal to some, but I'd prefer to spray.

[Ferretfancy]

Hunting by torchlight is rather bad form. I remember my father telling me about the time he went hunting tigers in India. The trick was to shine a torch when you saw two eyes gleaming in the darkness, and then fire between them. The only trouble was that after a while the tigers got used to this, and went round in pairs with one eye shut.

[umslopogaas]

The cads! That's unsporting.

[ardcarp]

One could of course fire a 12-bore at the cabbages. Chances are you'd pick off most of the caterpillars....and the holes in your crop would be no worse than those made by the little blighters.

[Dave2002]

Hunting by torchlight is rather bad form. I remember my father telling me about the time he went hunting tigers in India. The trick was to shine a torch when you saw two eyes gleaming in the darkness, and then fire between them. The only trouble was that after a while the tigers got used to this, and went round in pairs with one eye shut.

If true, and not a late or early posting for April 1st, then this might show that tigers have a theory of mind.

[Ferretfancy]

If true, and not a late or early posting for April 1st, then this might show that tigers have a theory of mind.

More a theory of appetite! Poor old dad was a soldier in India, but I doubt if he ever saw a tiger except in a zoo.

[mangerton]

Hunting by torchlight is rather bad form. I remember my father telling me about the time he went hunting tigers in India. The trick was to shine a torch when you saw two eyes gleaming in the darkness, and then fire between them. The only trouble was that after a while the tigers got used to this, and went round in pairs with one eye shut.

An oldie but goodie!

[Anna]

I was actually very shocked, my kitchen windowsill geraniums, being infested with caterpillars, their droppings visible and then, shock! horror! my windowsill frilly-leaf lettuce likewise - and, I discoverd about six caterpillars wriggly green creatures, which I plucked off and threw to the birds to devour ....
Nature is red in blood and claw. I have no idea how they managed to get insidel but I do feel guilty about it - they are all God's creature ....

[mangerton]

I was actually very shocked, my kitchen windowsill geraniums, being infested with caterpillars, their droppings visible and then, shock! horror! my windowsill frilly-leaf lettuce likewise - and, I discoverd about six caterpillars wriggly green creatures, which I plucked off and threw to the birds to devour ....
Nature is red in blood and claw. I have no idea how they managed to get insidel but I do feel guilty about it - they are all God's creature ....

I know what you mean. In that situation, then, best to follow the food-chain route that He has ordained, with no need to feel guilty.

[Anna]

I know what you mean. In that situation, then, best to follow the food-chain route that He has ordained, with no need to feel guilty.

Yes, you are right. I should have squished them on toast with a splash of balsamic and a strewing of rosemary and pepper. Yummy!

[gradus]

Have you tried netting the brassicas? It should be possible to keep butterfies out with netting of the correct mesh size, readily available on line. Enviromesh has the products to do the job: http://www.enviromesh.co.uk/

[doversoul1]

ardcarp
No, we don’t do organic. I use slug pellets quite extensively and some liquid feed from time to time.

umslopogaas
Thank you for your as ever detailed information. I have noticed that over the years, sprays and other pesticide that are available to non-commercial growers have become less effective and fewer in numbers. Besides, the size of my garden makes it quite impractical/uneconomical to use them. Caterpillars, like the badgers, have been part of this garden but this year, the damages from both are particularly noticeable. The odd thing is, there are very few butterflies this year. I have hardly seen cabbage whites.

Anna
I know what you mean. I tell myself that at least I do my best not to waste things I grow at the expense of other creatures.

gradus
Thank you for the link. I shall certainly look into it.

Well, the runner beans are almost coming to the end. This is an odd sort of a hungry gap before winter vegetables are ready. The badgers are still digging up my carrot patch (I have long given up the harvest). I wonder what they are finding.

[Eine Alpensinfonie]

One could of course fire a 12-bore at the cabbages. Chances are you'd pick off most of the caterpillars....and the holes in your crop would be no worse than those made by the little blighters.

That reminds me of the time when my sister was around 6 years old.
She said, "I don't like cheese with holes in it."
My father replied, "Don't worry, just eat the cheese and leave the holes."