Cabbage white butterfly

cwbuttfly  These flirtatious little butterflies can be destructive to stressed Brassica plants. If your plants have been attacked, squash any green caterpillars or feed them to the chooks. They often hide along the mid ribs of leaves making them difficult to see. Check daily for newly laid CWB eggs (bright yellow dots – usually on the backs of leaves), and brush them off. Also check for newly hatched larvae – these appear as fine green threads hiding under the leaves, and can look like leaf veins.

White cabbage moth attack is a sign that either:
1) Your plants could do with more water. Brassicas need thorough, regular watering – not a daily sprinkle. Mulching the bed reduces water loss and encourages horizontal movement of water through soil.
2) You have been a bit mean with the complete fertiliser when preparing the bed. Brassicas prefer a humus rich soil to provide a good supply of fertiliser. If they are not making steady growth, a side dressing of compost (under mulch) or applications of complete fertiliser, applied as a tea, can correct the problem. Or, they are missing some essential trace elements that you can supply with a drink or two of good quality seaweed extract tea (such as Acadian, Natrakelp or Seasol).
3) You have added enough fertiliser but the soil is too acid or alkaline for the plants to absorb what they need for pest resistance. If it is a case of too acid – and this can be remedied with an application of dolomite or agricultural lime. If you suspect acidity, apply a handful per square metre of bed and water it in. Avoid using hydrated lime on beds that contain plants as it can burn plant roots. If your soil is too alkaline, the addition of elemental sulphur will reduce alkalinity.
However, if they are making a total mess of your plants, apply Dipel while waiting for soil conditions to improve. Dipel will kill the caterpillars without killing good insects.

2 Replies to “Cabbage white butterfly”

  1. Thank you for this advice as just yesterday I noticed my little brassicas looking a little under the weather and I applied some seaweed tea as I had read in your book that healthy plants resist disease and reading this article assures me I applied the right first aid and gives me further advice as to what I can do if they don’t recover properly 🙂 Your book is fantastic and I actually found this site while googling it to see if I couldn’t suggest that you re-print it with further moon planting dates as I have recommended it to so many – and you’d already done it!!
    Thanks for your kind words, Jackie. 🙂

  2. Hi Just a question
    I think everyone will hate that we have “saved” some cabbage moth caterpillars, or rather my daughter has (she’s only 3 and absolutely loves the very hungry caterpillar book and adores the caterpillars she has saved from grandmas garden ( she was squishing them and this terrified my daughter, and the sweet sole she is, she had to save them) my question is though as stupid as it sounds as butterflies are the ones who lay the eggs but is it at all possible that a caterpillar could lay eggs as the caterpillars my daughter are in a container with tiny holes in the lid and I mean tiny tiny I made them with a red hot pin they havent been outside since she saved them they get their sun from the inside windowsill they have plent of food ant there is a bit of poop in the bottom of the container but on the underside of the lid there are now what look like tiny yellow cotton candies stuck to the lid with 2 of the caterpillars that have spent the past day on the underside of the lid one is staying quite close the eggs (they are definitely eggs) and the other has started to make a cacoon. This has confused me quite alot because the container has not got butterflys in it only caterpillars but all of a sudden there is eggs in the container
    Regards Danielle

    Hi Danielle, do you have photos of them?

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