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Welcome to our Head Gardener’s Journal

In this monthly column, we will share technical aspects of our work and also keep you up to date about ongoing projects. If there is any topic you might want to hear more about, please ask during your next visit!

Growing Brassicas without Cover

Growing brassicas is not for the faint-hearted gardener. Whilst the product is well worth the effort, a war must be fought on two fronts against the Cabbage White Butterfly, both small and large and the ever-persistent pigeon.

Butterflies might be beautiful, but their caterpillars are the nemesis for brassicas, with cabbages being a particular favourite. The Large Cabbage White caterpillar is by the far the more devastating and the presence of larvae should not be ignored as once hatched, they can reduce a plant to a mere skeleton overnight!

Pigeons can be one of the worst pests as they peck at leaves and tear at them often just leaving the stalks and larger leaf veins behind. Like ninjas in the early morning, they attack with stealth and accuracy while you are still safely tucked up in bed.

Cabbage White caterpillar damage and Pigeon damage

So, what preventative measures can be taken to avoid devastation? Covering the brassicas with netting is a common solution, but rather unsightly, so a more aesthetic answer can be the use of attractive bamboo cloche lined with netting. The problem with this is that the process of lining the cloche is quite tedious and ultimately the cloche will restrict the growth of the plants.

Bamboo and netting cloche restricting plant growth

This year we have applied two different methods to protect our brassicas without resorting to covering them in any way.

To counteract pigeon damage, we have strategically placed wind powered plastic owl decoys in our kitchen garden. Owl deterrents with mowing heads are proven to be the most effective and the use of these birds has most definitely kept the pigeons at bay and is an easy and cost-effective solution.

To counteract the Cabbage White Butterfly, we have applied a product called ‘Dipel DF’ which is a water dispersible, granular biological insecticide, ideally suited to the control of caterpillar infestations in brassicas.

Wind powered Owl and Dipel DF

We closely observe cabbage white presence around our vegetable patch and treat the plants as soon as eggs appear. As you can see, with the methods we have applied this year, our Cabbages have come through remarkably well and we are looking forward to the culinary delights they have to offer.

Our healthy brassicas