Cabbage White Caterpillars and Control

Since my last post I have been doing some web research and found that Cabbage White caterpillars are a pest from Oregon - where they are called cabbage worms and attack broccoli in particular - to Hobart, Australia (home of one branch of my husband's family).  I found a variety of biological control suggestions on the Australian site wwwglobalnetacademy.edu.au and from the Americans.  British sites such as www.growveg.co.uk were also helpful.  

I also realised that I may have inadvertently destroyed the cocoons of parasitic wasps that feed on the caterpillars, mistaking them for caterpillar pupae.  I will not do this again.  

All these methods from spraying bacteria to dusting baking soda mixed with flour looked to have some merit, although I regret that our house sparrows have not taken the hint and started to catch caterpillars.

All this is small-scale, very appropriate to our veg. patch and ecologically friendly gardening, but it leaves me wondering what is happening on our farms.  Consumers expect perfect broccolli free of frass (caterpillar droppings) so how is this achieved commercially and what impact are preventative methods having on the environment?

Finally, in the words of a television programme of my youth 'Don't try this at home, boys and girls'.  Please take this post as a personal reflection only, and take responsibility for your own gardening actions.  Thank you.

PS My husband is, even now, assembling the frames for the netting.

Brassicas and Butterflies

Leafing through the pages of our newly arrived August RHS magazine, I came upon an article on RHS Garden Harlow Carr, Harrogate.  (It's at some distance from here though I have visited when in that North Yorkshire town for a conference.)  What struck me was a reference to the kitchen garden - Nearby a fine black mesh protects the brassicas from pigeons and cabbage butterflies while also helping to keep them cool in hot weather.

The mesh method is the only ecologically-friendly way to keep cabbage white butterflies at bay.  Rushing out flapping a damp tea towel does not work.  Brandishing a fly swat in the shape of a plastic orange hand - now lacking several fingers - is futile.  Rubbing out newly laid eggs is not fail-safe.  Killing butterflies, an expedient of last resort by trapping them between a dustpan and brush only results in a fresh pair gaily performing a courtship dance above our remaining summer cabbage.

Once hatched the caterpillars are not content to stay on the tougher outer leaves of the plant.  They make their way to the tender hearts and start the process of destruction.  I am reduced to soaking what cabbage I can salvage in salty water.

This will not happen again.  Fine black mesh, rather than a stock of seeds, will appear on the next birthday present list.  We already have the plastic hoops to fit it over.

On the potting shed bench is a fine collection of kale seedlings, waiting to go out into a bed that has been duly rotated.  Kale is a member of the brassica family.  Caterpillars love it.  I too love most insects - but kale, along with beet spinach,  will comprise our winter greens.  Food will come first.