26-spotted ladybird

26spadult1 In hot, dry weather the 26 or 28-spotted ladybirds can do a lot of damage to the vegetable patch. Plants can only absorb nutrients from the soil as water-soluble ions. As soil dries out, vegetable plants are unable to absorb the nutrients they need to produce the compounds that deter pests, and these troublesome ladybirds can move in, feeding on leaves until only a network of veins remain. The larvae (pictured below) tend to feed on the underside of leaves while the adults feed on the upper sides of leaves. Badly damaged eaves can become papery, and brown. Their favourite foods are the cucurbit or squash family, which includes the melons. They can also attack, bean, potato and tomato plants.

The problem with using sprays to get rid of these pests is that whatever will kill them will also kill the beneficial ladybirds that help keep many garden pests under control, including the bright black and yellow ladybird that eats powdery mildew and other fungi. Fungus-eating ladybirds are often seen wandering over leaves of the squash family.
The Brisbane Insects website now has a field guide to ladybirds to make it very easy for you to identify whether the tiny creatures crawling on your plants are pests or ladybird larvae, which come in a range of colours and shapes.
Click here: Ladybird Field Guide

The best way to solve the problem of 26 (or 28)-spotted ladybirds is to knock the adults and their larvae into a soup tin with some methylated spirits in the bottom of it. Also scrape off the eggs, which can be found in a cluster on the underside of leaves (see photo below).
Then give the foliage and soil around the plants a generous drink of seaweed extract tea, to supply potassium and trace elements plants need to build resistance to pests, because only stressed plants are attractive to pests. Ensure the plants have sufficient fertiliser for healthy growth, and that the soil is not too acidic or too alkaline. Water the plants thoroughly, under mulch, when the top cm. of soil is dry, rather than giving them a lighter, daily watering. If drought conditions are making it difficult to spare enough water, you can help deter them by spraying both sides of the leaves with chilli spray, but you will need a lot of chillis. The solution is – 2 cups chillis to 2 cups of water. Chop chillis finely while wearing gloves. Steep them in water for an hour, strain mixture, and spray liquid over leaves. (Garlic spray can be used as a deterrent but breaks down quickly in hot weather.) Finally, get rid of any blackberry nightshade plants. These act as a host for this little pest. See:Blackberry Nightshade
26speggs1 26splarvae1
Eggs and larvae of the 26 (or 28)-spotted ladybird.

7 thoughts on “26-spotted ladybird

  1. Hi. Wonder if you can sort this.
    1. Most fungi need moisture and organic material. This seems to be supported by my zuccinis which seem to get worse powdery mildew when I get water on the leaves. I have read that they like dry weather. Is there evidence for either opinion?
    2. Some people say that the ladybirds that feed on this mildew spread it by carrying spores, others reckon they are a controller, eating the fungus down. What is the evidence please for either of these?
    Many thanks.
    Barb
    Barb, the answer to your questions can be found in this post: Powdery mildew on zucchini

  2. Thank you so much for this information – I’ve been doing some searches regarding the larval stage and wasn’t able to find very much about it. The photos were also helpful to identify this pest in our pumpkins / melons.

  3. Thank you for this information. I have finally found out that these are NOT the good guys and will now go happily about using the chilli spray and the squish method on the affected crops.

  4. Barb,
    To answer your questions:
    1. Try not water the leaves, and perhaps pour water down below the leaves. Don’t water too often – a good soaking once in a while to maintain the soil moisture is sufficient. Mulch, mulch, mulch. It will keep the soil moist and cool. Make sure they’re spaced out as well, to let air circulate around them.When plants are putting out flowers and fruit, they focus on that primarily, as they want to reproduce. By watering too often you’re asking the plants to grow more leaves, and as a result put energy into leaves and not into fruit.

    2. The little yellow and black lady beetles eat the mildew off the top. The spores are below – and the larvae also eat the mildew, and I often see them underneath the leaf.
    Spores are spread from rain or water splashing on the leaves.

    Hope that helps 🙂

  5. Leaf-eating ladybirds: Very useful article, thank you. I was able to identify the pests eating my spinach. The beetles in my garden look somewhat different (large brick-red spots on a dark background), but the larvae are the same yellow ones as in your photographs.

    Jan Stemmett
    Polokwane
    South Africa

  6. Thanks soo much for this informative post!!! I have been squishing the larvae and taking no notice of all the ladybeetles. We are in central Queensland so hot dry conditions exactly like this article says.

  7. Yes not so hot here this time of year in perth near the coast but my nightshade is full of them thanks for the info I will feed em to the chooks

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