Houseplants often suffer from infestations of bugs and insects in the potting compost. All houseplants can suffer but cacti, succulents, geraniums and fuchsias are particularly liable to be infected.

Treatments differ depending on the particular bug which is in the soil. However, almost all soil borne bugs thrive in particular conditions. Change the soil conditions and many of the bugs will simply disappear. We identify the key soil bugs and advise you on how to treat them effectively.

 

General Treatment for Soil Pests
Most soil pests prefer damp conditions in the soil. Some pests prefer drier conditions, but these pests live near the surface of the soil. With these factors in mind, gently ease off the top 1¼cm (½in) of soil / compost and throw it away. Replace it with half the amount of new compost and cover that with grit to the previous level of the soil. That may well get rid of many of the soil pests and the grit on top will put them off further. Keep the plants slightly under-watered.

Move the plant to a new position because some airborne soil pests may well still be flying around just waiting for you to return the pot to its previous position. Also, keep affected plants away from healthy ones.

More drastic general treatment is to remove all soil from around the plant roots and stem then re-pot it brand new compost. This should get rid of most soil bugs but the shock may well kill a plant weakened by them. A more gentle way of removing some soil pests is to take the plant and compost out of the pot (when the compost is on the dry side) and inspect the outside of the compost. If you see any bugs, gently remove a small amount of the outer soil, with any visible bugs and dispose of it. Re-pot with a small amount of compost replacing any which has been been removed.

Soil Mealy Bugs (Rhizoecus of various types)
IDENTIFICATION
Adult soil mealy bugs are around 2mm (eigth of an inch) long, normally white and a long oval in shape. They look like a small grain of rice. They are covered in a powdery white wax. Their movements are very restricted.

TREATMENT
If the general treatment above does not work then you will need to resort to insecticides to get rid of soil mealy bugs. Two proven products are Bayer Provado Vine Weevil  Killer and Scotts Bug Clear Ultra Vine Weevil Killer. Both are systemic and both will provide protection from other bugs and insects. They are widely available in the UK online and in most garden centres.

Springtails
IDENTIFICATION

 

TREATMENT
See general treatment above if you want to get rid of springtails.

Vine Weevils
IDENTIFICATION
The adult vine weevil is often apparent on the top of the soil but not underneath. They eat leaves and damage is easy to see as notches eaten into the leaves. Far more damaging are the small (10mm) white plump larvae which can be found in the soil / compost. These will eat the roots and eventually kill the plant. Both adult and larvae will be present at the same time.

TREATMENT
Nematodes are available online and in garden centres to kill vine weevils. Chemical controls are Bayer Provado Vine Weevil  Killer and Scotts Bug Clear Ultra Vine Weevil Killer which are readily available in the UK.