Both aphids and whiteflies suck, literally. They are close relatives in the world of sucking pests, the aphid belonging to the superfamily of pests known as the Aphidoidea and whitefly to the Hemiptera, but both love to feed on the sap of your edible plants. Favoured plants are usually members of the gourd and nightshade families; meaning your pumpkins, cucumbers, squash and zucchini, along with tomatoes, eggplant, capsicum and chilli respectively. 

Aphids

Optimal conditions: wet and warm (also known as spring)

Signature: clusters of small black or green dots on the stems of your plants and underside of the leaves. Turns the leaves yellow by sucking out their sap and then leaves behind a sugary residue - called honeydew - that ants feed on. An abundance of ants, that then protect the aphids, is a tell tale sign of a problem.

Aphids are semi-microscopic pests - seen with regular eyes or better with a microscope - that come as predictably as the change of season. Each spring as the weather warms up and rains fall in greater volumes, the aphid population rises faster than your pumpkin seedlings. In a blink of an eye, many hundreds of aphids take up cover and a feeding spot on your plants eating them from the inside out.

When eating, they create a sugary substance called honeydew, that then feeds their no.1 ally, the ant. If you happen to notice ants scampering up and down your plants, you can be sure that aphids are somewhere to be found.

Whiteflies

Optimal conditions: wet and warm (also known as spring)

Signature: brush against a plant and a million tiny white flies momentarily become airborne before returning to their sucking

Whiteflies behave in a similar fashion. The adults and their larvae simply love hanging out on the underside of leaves and suck sugary phloem juices all day. When disturbed they kind of flutter about a bit - performing an impromtu, but well organised Mexican wave - but soon want to be back in sucking position. Not only do they suck the life out of plants, they are also vectors for viruses which causes nasty plant diseases.

Adults live four to six weeks and lay over 100 eggs each (onto the underside of the leaf), so each plant can be quickly populated by an army of the white suckers. All in all, you want to make sure they don’t get too comfortable.

But remember that the whitefly and aphid are both seasonal pests that peak when conditions are ideal and then (usually) abate when the weather changes. This doesn’t mean you should sit back and do nothing, it just means not to freak out.

The worst thing you can do is begin spraying with chemical fixers which will discourage predators to come in and help. Rather ensure there is high diversity of different border-plants and flowers, particularly nasturtiums, which attract predators that become your secret helpers. This is not just some pseudo science stuff; professional growers constantly utilise this ‘free labor’ by strategically planting border plants to attract certain bugs. The ladybird is a huge ally.

Prevention: Keep the plants well spaced, allowing passage for airflow rather than the perfect, air-locked breeding ground. Consistently water, in the morning rather than the evening when all pests are more active. Don’t overfeed with nitrogen which tends to make plants more susceptible. Mulching the soil well will also help break the breeding cycle as this is where they lay their eggs.

Coping: they are attracted to the colour yellow like girls to diamonds, moss to stones, snot to a toddler’s nose. Hang yellow sticky traps around the concerned plants and they will fly onto them and get stuck. One sucker after another. Regularly clean the affected plants with a soapy spray to clean the leaves of both pests, the honeydew and the ants. 

Eradicating: An organic white or eco-oil will help to eradicate the whitefly but alway make sure to spray the underside of all leaves. Nicotine sprays have also been found to work. The old hippy method is to soak ciggies in water overnight and then use the water in a spray bottle. But that's pretty damn gross, so we prefer using eco-oil.