The old ‘prevention is the best method’ rings true with plant pests and diseases. A good quarantine protocol allows for new acquisitions to be kept separate from the rest of the collection so that disease and damage are kept to a minimum. This means ideally in a separate room, or at the very least, a separate bin or rack. There are various degrees to which you can keep plants separate, the most thorough being one plant per (sealed) container. This is not always the most practical way of quarantining because it takes up more space than housing plants communally. I house plants based on their source and date of arrival for a minimum of six months, but more often than not, this ends up being their permanent home. Some pests do not become evident until months after you receive them, either because they were cleaned before sending, or because eggs have not yet hatched. It is not uncommon for aphids eggs to sit in soil or on plant surface for six months.
For nearly a decade I did not use any pesticides on my indoor or outdoor plants. In the past year, I have had new plants come in with multiple types of aphids, including ground aphids and one that resembles a bean aphid. The bean aphids were on imports out of Asia and came in bare-root without any observable sign of disease. The ground aphids were from a reliable domestic source, and especially difficult to keep track of due to their subterranean breeding and activity. Thankfully, all plants were housed only with other plants from the same import/shipment. Nonetheless, it was still a considerable number of plants infected, as this spring the plant collection has grown considerably.
For six months I attempted to eradicate the aphids using natural methods including vinegar, insecticidal soap (potassium salts), peroxide, neem oil, and various submersion techniques. The plants suffered from excess moisture from the frequent mistings, and the aphid populations were not declining. I also tried hand cleaning over 600 plants with a mild soap/neem solution and repotting in new substrate. It took over two weeks standing at a sink all day to clean them. The aphids kept coming back. I repeated the treatments, combined treatments, for months, without success. The aphid populations were never high, but they were persistent. As a last resort, I tried a systemic insecticide to treat both the ground aphids and the bean aphids using a very dilute dosage (1/10 teaspoon/gallon). For most plants, one treatment was all that was required, but a few required a second dose. It took care of both aphid types in a matter of days and there has been no sign of them since.
I offer this as a word of caution, to always quarantine new plants, and also to say that I am fastidious about checking for diseases and pests. I only ever sell plants that I am confident to be pest and disease-free. The only pest that has been problematic to me, as described above, are aphids. Over the course of the past six months, I have treated many of my newer species because the source plants contained aphids. *If you have purchased any plants, out of caution for animal terrarium inhabitants, please refrain from putting them with live animals for six months.* I realize this is less than ideal, and do not anticipate this precaution to be required in the future.