I love butterflies but with one exception, the dreaded Cabbage White Butterfly. If you have ever grown cabbages or any other brassica you’ll know what I’m talking about.

I have seen first hand the devastation the cabbage white butterflies and their caterpillars can unleash on my Brussels Sprouts two years ago. I was a beginner Brussels sprouts grower and didn’t realise these vegetables need a fort knocks vault of mesh or small holed netting around them to stop any cabbage white butterflies from entering.

I grew red cabbages with success with blue water pipe hoops and environmesh over it pegged down with ground staples and kale in cube aluminium tubing cages with butterfly netting over them.

However when it comes to Brussels sprouts, I have realised you need the tallest cage necessary as some of the plants reach at least 1 metre high and a cage where the mesh or netting doesn’t touch the plants otherwise your doomed.

If the netting touches the plants, the cabbage white sits and sprays its yellow eggs on the leaves near the netting and if you don’t spot the yellow eggs within 2 weeks the caterpillars hatch and munch all your plants.

Maintenance of the Brussels sprouts cage is always risky and I’m sure thats how butterflies have sneaked in before, when the netting has been opened up. So I aim not to open the cage or netting unless it is absolutely necessary. I also hope the boundaries will not be broken by cabbage white butterflies either.

Netting Options for your Vegetable Cage or Tunnel Hoops

1. Environmesh

This is white agricultural grade mesh with 1.3-4mm holes.

Advantages:

• Very thin holes, so virtually no pests will be able to get through to your crops.
• As the netting is thick, it protects against wind, heavy rain and frost.
• You can still water through the netting and it lets air and sunlight through so it doesn’t needs removing apart from weeding.

Disadvantages:

• As the environmesh is thick, it cannot be put over a cage very easily and isn’t very flexible. It is better used over hoops for a crop tunnel.
• As the mesh is thick, you can’t see the crops very well through the netting and is isn’t aesthetically pleasing to look at as it doesn’t blend into the environment by being white.
• Like all other netting, if you are weeding, you will have to lift the netting, which a butterfly might try and get in whilst you are doing this. They are sneaky little butterflies!

2. Black or Green Butterfly Netting

This netting comes in black or green and has 4-7mm size holes

Advantages:

• The netting is more flexible so can be put over a vegetable crop cage or a cube shaped area.
• You can see your vegetables growing through it.
• Insects can still fly through the netting.

Disadvantages:

• There is a risk that if the butterfly sprays the eggs through the netting it could hit the plants.

My ‘Keep out the White Cabbage Butterfly’ Cage Trial

This year I am trialling an aluminium tubing cage with black butterfly netting over the top, pegged into the ground with metal ground staples. The butterfly netting is the 4-7mm wide holes which should prevent cabbage white butterflies as long as the plants leaves don’t touch the sides of the netting.

The cage is 1.2 metres long by 90cm wide and I have planted 4 plants in a rectangular shape in the middle of the cage. I used this cage last year to grow my kale plants in from august and overwinter and it was very successful.

I am keeping my fingers crossed the butterfly netting is enough to keep them out this year, I’ll update you later on in the Summer.

Recommended Vegetable Cage and Netting Supplier in the UK

I bought my aluminium vegetable cage and black butterfly netting from Garden Naturally.

My vegetable cage was under ‘Build your own cage’ and built with 19mm pole diameter uprights of 1.2 metre high and 19mm pole diameter cross sections of 90cm length (the width of my raised beds). The poles were put together with the 19mm black joiners and I used the aluminium anchors to make it secure in the raised bed. The netting is called Soft Black Butterly netting and they also sell an equivalent to environmesh called Veggiemesh. I have previously bought my environmesh from Amazon.