How do I know it's aphids and not something else?
Look at the back end. Aphids have two tiny tubes (cornicles) pointing backward from the rear, and nothing else on a houseplant does. Color doesn't tell you much, since aphids can be green, black, pink, yellow or grey. White wax with no tubes is usually mealybugs, and flat, still ovals on the leaf undersides are whitefly nymphs.
Which Aphidius wasp do I need?
It depends on the aphid, not its size. Aphidius colemani is for green peach and melon aphid. Aphidius ervi is for potato, foxglove and pea aphid, which colemani can't develop in. Aphidius matricariae is for green peach aphid in a cooler room. If you can't tell which aphid you have, choose Aphidoletes, which works on over 60 species.
Why did my ladybugs fly away?
That's normal. Most adult ladybugs leave within a day or two, even when there are plenty of aphids, and it says nothing about your plant. Release them at dusk on the lower stems after misting the plant, and they eat a lot of aphids before they go. They're a quick knockdown, not a standing guard, so follow up with Aphidius.
What are the tan, papery aphids on my plant?
Those are mummies, and they mean the Aphidius wasps are working. Each one has a wasp developing inside. Leave them on the plant until you see a small round exit hole, because every one that hatches goes on to parasitize more aphids.
Do I really need to deal with the ants?
Yes. Ants farm aphids for their honeydew and defend the colony, carrying off or killing the predators you release. A ring of sticky tape or a line of diatomaceous earth around the base of the stem stops them. Do it before you release anything.
How often should I release predators for aphids?
Every 2 to 4 weeks while aphids are active. Aphids breed fast, so one release rarely finishes them. Keep going until the new growth stays clean two weeks in a row.
Can I use sticky cards and sprays with aphid predators?
Take yellow sticky cards down, because they catch the wasps and midges. Neem oil and insecticidal soap are fine to follow after one day. Skip systemic insecticides, which poison the aphids the wasps develop in, and never use sulfur with these predators.
Will aphids die off in winter indoors?
No. Outdoors, shortening days switch aphids to laying eggs that overwinter. Indoors, warmth cancels that switch, so an indoor colony keeps giving birth all year.
Do these predators work on root aphids?
Root aphids live on the roots, out of reach of predators that hunt on leaves, and there's little research on treating them. White wax on the roots and winged aphids turning up on sticky cards are the usual signs. Isolate the plant, check the root ball, and isolate new plants before they join the rest.
What are the spiky black-and-orange bugs on my plant?
Those are ladybug larvae, and they eat even more aphids than the adults. They hatch from eggs your ladybugs laid before leaving. Don't spray them.
Are aphid predators safe around pets and people?
Yes. Aphidius wasps are tiny and can't sting people or pets, and none of the predators we sell damage plants. Ladybugs, lacewing larvae and aphid midges feed on aphids and other small insects, not on you.