Aphids on Chili plants
Many thanks for your message regarding the aphids on your chilli plants. Before you introduce ladybirds to combat the attack of aphids, we would recommend that you attempt to remove them by other means. Any organic insecticide should give good results as these sprays work by suffocating and smothering the pest, and therefore it is impossible for any resistance to build up. If you are going to attempt a further application, please ensure that you spray both sides of the leaf, as some aphids may be sheltering on the underside. We can recommend the Natural Bug Killer GPC-500, which we have used to good effect in our own Kitchen Garden.
Alternatively, you may wish to wipe the stems where the aphids tend to congregate wit a tissue and physically remove or crush the aphids in this manner, or spray each plant with jets of water to dislodge the pests. A further alternative is an application of derris, either by spray or dust, the strongest organic insecticide available. However, some groups of pests have established some resistance to this control measure.
If these methods do not remove your pests, then you can consider using the ladybirds! We would recommend that you use the larvae as if the plants are on a kitchen windowsill, it is likely that adult ladybirds may fly outside to greener pastures. The larvae will probably to remain on your chillies for a longer period and are very aggressive predators of aphids.
Finally, it is extremely unlikely that the aphids are interested in the soil as they live by sucking sap from the plant. However, there are some species of aphids that do emerge from the soil so it may be worthwhile re-potting your chillies with new compost in the near future.
Hopefully this information will prove to be of help but if you require any further advice, please do not hesitate to contact us.
Many thanks once again for your enquiry and we wish you the best of luck!