Q: Some of my houseplants have spent the summer outdoors. When should I bring them inside and what should be done before bringing them in?
A: Although summer heat may linger into September, average daytime temperatures are falling, and soon the daytime highs will be similar to indoor temperatures—an ideal time to move plants inside with minimal stress. Tropical plants must come indoors before overnight temperatures drop to 45 to 50 degrees Fahrenheit, depending on the species of plant. All other plants should be brought inside before daytime temperatures drop below 60 degrees.
To prevent future problems, plants need the following care before coming inside. Beginning this process now reduces the chance of a mad dash if temperatures drop unexpectedly.
Cleanup. Remove dead or damaged foliage and trim back plants that have become too large or overgrown. Never remove more than one-third of the growth at one time. Inspect the plant’s container for damage and remove any dirt, mineral deposits, and fungal or algae growths.
Find and eliminate pests. Carefully inspect each plant for insects and eliminate them before they come indoors and infest your other houseplants. Common pests include aphids, mealy bugs, scale, and spider mites. Chemical-free treatment options include using a spray bottle to wash off the insects from the entire plant, or for hardier plants, dunking the entire plant, pot and all, in a bucket of water for several minutes. These steps may need to be repeated.
Insecticidal soaps, available at garden centers in premixed spray bottles, are a lower toxicity insecticide that will effectively treat most houseplant pests. Be certain to read and follow safety and application instructions included with the product.
Repot only if needed. Repotting can stress a plant and should be done only if a plant has outgrown its pot. Repotting is best done in late winter/early spring before plants resume active growth.
Please email firstname.lastname@example.org with specific houseplant and pest control recommendations.