It begins with a small, unassuming midge — about 2mm long, easily overlooked, hunting silently through your borders. She's looking for aphid colonies, and when she finds one, she lays her eggs right beside them. What hatches a few days later is unmistakable: bright orange larvae, vivid against the green of your plants, working their way through the colony with quiet efficiency. Up to 60 species of aphid are on the menu.

This is the Aphid Midge (Aphidoletes aphidimyza) — one of nature's most effective aphid predators, and one of the most satisfying biological controls to watch in action. Particularly valuable in early and late season, when other beneficial insects haven't yet woken up or have already retreated.

How it works

You receive aphid midge cocoons in a small ventilated box. Tear open the back of the box, place it amongst your plants in a shaded spot, and let the adults emerge naturally over the following days. There's no spraying, no watering-in, no mixing — just release the cocoons where the aphids are and the midges do the rest.

Each emerging adult female (around 2mm long) actively seeks out aphid colonies and lays her eggs directly next to them — a remarkably accurate piece of natural pest-control engineering. The eggs hatch into highly visible orange larvae that feed on the aphid colony, injecting a small amount of paralysing fluid that dissolves the aphid's body contents. Larvae mature over 7-16 days, then drop into the soil or compost to pupate. New adults emerge 10-14 days later, ready to begin the cycle again.

The result is a self-sustaining little population that can keep working in your garden for several generations — provided the aphids hold out long enough to feed them.

What they tackle

Aphid midge larvae feed on up to 60 species of aphid — including the most common garden trouble-makers:

• Black aphids on broad beans and dahlias
• Green aphids on roses, lupins, and chrysanthemums
• Cabbage and lettuce aphids on edible crops
• Woolly aphids on apple trees
• Greenhouse aphids on protected crops

Particularly useful for early-season outbreaks when ladybirds and lacewings haven't yet arrived in numbers, and late-season populations that build up after other predators have wound down.

Early intervention works best

The traditional advice for aphid midges is to release them at the first sign of aphid activity, rather than waiting until colonies are well established. A small dose released early can prevent a problem from developing into a full-blown infestation that needs much heavier intervention. If you've spotted the first aphids on a rose bud, the soft new growth of broad beans, or a single cluster on a chrysanthemum — that's the moment.

For larger or already-established infestations, the supplier recommends releasing in staggered doses over a few weeks rather than deploying everything at once. This keeps a continuous adult population working on the problem and gives the second generation something to emerge into.

How to release

1. Tear open the back of the box so the midges can fly out as they hatch.
2. Place the box on the ground near affected plants, or hang it amongst the branches.
3. Choose a shaded spot — out of direct sun, sheltered from rain.
4. Angle the opening so water can't collect inside the box.
5. Leave the box in place for the adults to continue emerging over several days.

Dose: approximately 1 cocoon per square metre is the standard rate. For a typical infested rose, broad bean row, or small greenhouse, the 250-cocoon pack is usually sufficient. For larger areas or whole-greenhouse treatment, the 1000-cocoon pack offers better value per cocoon.

Full release instructions come with your pack. You can also download the detailed instructions here.

Conditions for success

Aphid midges thrive at 20-26°C with reasonable humidity and an established aphid problem to feed on. Adults feed on aphid honeydew (the sticky residue aphids excrete), so a population needs an existing pest issue to thrive. Dry conditions shorten the adult lifespan; shaded, humid spots prolong it.

• Outdoor use: April to September. Most effective in greenhouse-style protected conditions and warm garden microclimates.
• Greenhouse use: usable year-round in heated greenhouses; ideal for protected crops with aphid problems.
• Adult lifespan: 7-10 days per adult, but the cycle continues through multiple generations.

Apply in the cool of evening rather than the heat of midday — opening the box at dusk gives the first emerging adults a calmer environment to orient themselves in.

Pack sizes

• 250 cocoons — available March to September only. Suitable for small gardens, individual problem plants, or first-response intervention.
• 1000 cocoons — available year-round. Suitable for larger gardens, whole-greenhouse treatment, or winter greenhouse aphid problems.

Ordering and despatch

Because aphid midges are live biological controls, we don't keep them on standing stock — they're ordered in fresh through our partner Ladybird Plant Care so they reach you at peak effectiveness.

• Order by 10am Monday for despatch the same week
• Orders placed after 10am Monday will despatch the following week
• Dispatched directly by Ladybird Plant Care — you'll receive tracking from them

Worth bearing in mind if you're racing an aphid outbreak — give yourself a few days' grace between ordering and treatment.

About Ladybird Plant Care

Ladybird Plant Care are specialists in biological pest controls — gentle, naturally-derived solutions for problems that have traditionally been tackled with chemicals. We work with them through a direct fulfilment arrangement, which means your order ships from their refrigerated facility to your door at peak freshness. We've chosen them as our biological-control partner because their approach mirrors our own: work with the garden, not against it, and trust the wider ecosystem to find its own balance.

A note on watching it work: the bright orange larvae are one of the most visible and satisfying signs of biological control doing its job. If you spot them on your plants over the days following release, that's exactly what should be happening. Resist the urge to wipe them off — they're the answer, not the problem.

Live biological products cannot be returned. Please order only when you're ready to release within the next few days, and ensure you have suitable conditions (moderate temperatures, existing aphid activity) for treatment success.