A Potato Ladybeetle is a beetle belonging to the ladybeetle family (Coccinellidae). It's a medium-sized beetle, measuring only 8mm when fully grown, possessing 20 large, red spots in total. Despite the many beneficial members of the family, this particular species eats the leaves of tomato and potato plants. The larvae feed on the same parts of plants as the adults, doubling the damage! Both will graze beneath the surfaces of leaves, so can go unnoticed by gardeners.
These ladybeetles are pests of tomatoes and potatoes.
Potato Ladybeetle normally attack the leaves of plants, sparing the fruits.
A Potato Ladybeetle looks similar to any other beneficial lady beetle. This can make it difficult to separate the good guys from the bad. Here are a few simple tricks to help you correctly identify a Potato Ladybeetle. Potato adults are pinkish-orange-red. A beneficial Chequered Ladybeetle is more yellow than red. They possess 10 pinkish-orange-red patches per elytron (protective wing case). A beneficial Chequered Ladybeetle also has 10 yellowish spots, however, also possess 2 additional spots on the pronotum (segment following the head). A Potato Ladybeetle is not as shiny as a Chequered Ladybeetle. Larvae tend to be yellow, covered in black branched spikes that look like a frizzy outline. Like the ladybeetle, they have six legs too. They have previously been compared to tiny, yellow grubs! The eggs are so small; gardeners often miss them. They tend to be bright yellow, oval, and attached firmly to the bottom of squash leaves. They can easily be mistaken for beneficial ladybeetle eggs, so it may be worth monitoring or moving them to another plant before you squash them.
You may see tiny 'yellow grubs' crawling beneath the leaves of vegetable plants. These insects feeding will reduce the amount of nutrients a plant receives. Leaves may become skeletonised from gregarious feeding. Heavy infestations may stunt plant growth, with additional losses of plant vigour.
Unfortunately, Potato Ladybeetles are vegetarians. This means both the larvae and adults feed solely on the plant leaves. Good housekeeping can help to prevent an attack. By rotating crops, you can confuse beetles who return the following year. Likewise, clearing any debris in autumn can remove any overwintering beetles. For pest caterpillars, it's suggested picking them off and squashing them first. This is the best way to ensure you are not removing the good ladybeetles too. It's advised to wear gloves because these insects squirt a smelly liquid when threatened. Capturing natural enemies and releasing them on the affected area may improve infestations. These include insects like spiders, mantids, wasps and other predatory beetles. By letting some parts of the garden 'grow wild' paired with an abundance of pollinator-friendly plants, you can attract the latter into your garden. Homemade insecticidal soaps can be advantageous if applied regularly over several intervals. Vegetable oil and a drop of fairy liquid can be diluted with water. If you aren't sure of your ID, pop your insect in a bug pot or beneath a glass and ask the Candide community! Once ID'd, you can decide what to do!