Hi Marjie –
Scale insects are common on โmany โhouseplants and often build up unnoticed before plants begin to show damage.The good news is, that most adult scales live and feed under their protective armor covering and do NOT move about the plant. However, care must be taken that โtheir โโmobile nymphs, sometimes called crawlers, do not migrate out from under this covering and attack other โparts of the โsame plant โor even nearby plants.
To prevent and treat many insect pests, including scales, on indoor plants we strongly recommend neem oil.โ โCold-pressed from the fruits, seeds and bark of an evergreen tree (Azadiracta indica) native to India, neem oilโ โis 100% natural and safe to use. It will not persist in the environment and is โnon-toxic to people, pets and many beneficial insects.
Easy to use, just mix 1/2 – 2 tsp per quart of warm water with a couple drops of mild dishwashing soap (used as a surfactant) and spray the diluted solution generously over all leaf surfaces, including the undersides. Apply every 2-4 days for a two week period. This schedule will help break the life-cycle of many indoor plant pests commonly found on houseplants. Do NOT apply in direct sunlight or under plant grow lights.
Good luck!