By Millie Hurst published
Many gardeners will already be looking ahead to the leaner months and planting out some lovely winter brassicas. The kitchen staples – from cabbages to cauliflowers and turnips – are also favorites among troublesome flea beetles.
Here, an expert shares a tip on how to stop them from wreaking havoc on your patch.
If you're thinking of sowing radishes, turnips, or swedes, or maybe you're planting out winter cabbages and kale, beware of flea beetles. The pests are drawn to any plant that's a member of the brassica family, and particularly like seedlings.
The flea beetle will make lots of small 'shotholes' in the leaves of seedlings, which may not be able to recover. 'While older plants are tolerant of damage and readily grow out of symptoms, seedlings are not and can become overwhelmed,' says Lucy Chamberlain, Amateur Gardening magazine's fruit and vegetable expert.
'The simple solution? As soon as you see signs of damage, smear grease over some short rectangles of cardboard and run them over your seedling rows,' Lucy says.
'As the flea beetles are disturbed, they jump – and meet with their sticky end. Job done!' The trick works because of the fact flea beetles are able to use their long back legs to jump several centimeters in the air when threatened – just like a flea.
Flea beetles don't like basil, so if you already have a pot of Mediterranean herbs in your garden, try moving it nearer to your vegetable patch. Head to our guide on companion planting for advice on which plants might grow well together.
Plus, our step-by-step on how to grow cabbage has lots of tips so you can avoid other common problems.
Amateur Gardening magazine expert Ruth Hayes can confirm from experience that the greased cardboard trick works well in deterring these pests. 'Flea beetles are an absolute menace and attack a wide variety of plants and crops, as I have learned to my cost,' she begins.
'I would much rather use organic controls than pesticides, so my go-to method of removing them is to smear a square of cardboard with grease or insect barrier glue, attach it to a cane and sweep it over the beetle-affected plants.
'As they jump to avoid it, they stick to the card, which is incredibly satisfying to see, and also demonstrates the severity of the infestation. If it's bad, repeat the procedure as necessary,' Ruth says.
For the full rundown on growing brassicas, head to our guide on how to grow winter brassicas. And to prevent flea beetles from getting to your vegetables in the first place, you could try covering your vegetable patch with a row cover.
As long as it's attached securely, it will prevent any other insects from reaching your crops and keeps the temperature a little warmer at night.
Millie joined Gardeningetc in early 2021. At this time of year, she enjoys getting festive with some wreath making and loves creating a vibrant display of containers in her small urban garden. She loves picking up new plants at the local garden center and is never without some fresh flowers at home. Her favorite houseplant is her variegated pothos that's currently climbing its way over her bookshelves.
Snake plant care and growing tips: expert houseplant advice
Plants Our expert guide has lots of practical tips on snake plant care so you can ensure this much-loved houseplant will thrive in your home
By Sarah Wilson • Published
Types of camellias: 12 beautiful varieties of these flowering shrubs
Plants Our edit of the different types of camellias will help you choose the best one for your flowerbeds and pots
By Graham Rice • Published