Blog posted by Dominic Murphy

Last week, I wrote about our late gamble with winter salad. Just seven days later, and three of our eight containers have germinated already (the rocket and mixed salad leaves, since you ask). It’s not quite the jackpot, but so much better than I hoped, and just the thing to engage the children. Now, even though it’s got a lot colder, I’m tempted to plant some more.

There is less promising news from the cabbage bed (see September’s blog), where caterpillars, slugs and, I suspect, pigeons have combined to make a sorry sight. There are now many skeletons where once stood young brassicas, and most remaining plants are sporting the colander look, their leaves riddled with holes, their lives hanging by a thread.

It seems too cold for caterpillars, and there is no sign of them on the plants, which just leaves the birds and slugs. I wrote a bit about slugs last term, but not about the best design for a beer trap. Often these are badly designed which means they don’t work properly, killing useful creatures and filling up with rainwater, too.

The best beer trap is made from a plastic container with a lid, say a pot of margarine or hummous. First, cut out sections at regular intervals around the rim so that the top resembles the crenellations, or battlements, on a castle. The holes you have made should be big enough to fit a slug. Now fill up the container as far as the lip of the battlements, put on the lid and bury the the whole thing slightly in the ground, making sure the bottom of the battlements are raised above the soil surface.  This design should mean that no inquisitive frogs should fall in the top, while nice insects like ground beetles will not wander in at the sides. You don’t have to stick to beer: any sweet liquid, such as a solution of jam and water, is supposed to work, and I have been successful with cider (usually cheaper than beer).

For the pigeons, we have put up netting, stretched tightly over bamboo canes that have been planted around the sides of the bed. To deter the birds further and avoid them getting caught in the nets, old CDs are suspended on string across the middle.

And all this for a bed of cabbage.

Dominic Murphy’s book The Playground Potting Shed: A Foolproof Guide to Gardening with Children is published by Guardian Books, priced £12.99. To order your copy for £10.99, visit guardianbooks.co.uk or call 0870 606 4232.