Bonsai Tree Pests

Pests on a bonsai tree


Aphids (blackfly, greenfly and whitefly) are sap sucking insects which rarely cause a problem for bonsai. Aphids are very easy to identify and easy to treat, so are no cause for alarm. They are more commonly spotted in spring/early summer.
Usually the first sign of aphids is shiny sticky patches on the top surface of the leaves. This is caused by honeydew which is excreted by the insects and drops from the leaves above (see photo 1).
Sometimes black sooty mould grows on the honeydew (see photo 2).
White skin casts can sometimes be seen on the top of the leaves (they can look like a strange insects but are just empty aphid skins). (See photo 3).
It is usually possible to see the aphids, they tend to colonise on the shoot tips (see photo 4).

We recommend that you spray weekly with a Plant Invigorator to prevent pests such as aphids developing.

Should you find that your do have aphid on your bonsai, please do not worry, simply purchase an insecticide from your local garden centre and follow the instructions. If you do not want to spray you can simply pick the insects off the shoots (keep checking that more do not hatch).

Aphid on bonsai tree 1 Aphid on bonsai tree 2 Aphid on bonsai tree 3 Aphid on bonsai tree 4

Scarid Flies...

Scarid flies are not uncommon on seedlings and house plants. They are grey/brown flies which live in the soil surface and do no harm at all. Keeping the soil surface barely damp (and not wet) will discourage them. If you find them annoying simply spray with an insecticide. Occasionally you may spot a larvae, it is small, long white and slender. These flies are not something to be concerned about; they are rarely noticeable after a few days.

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