Follow these tips for bringing 'outdoor' houseplants back indoors
We are in late September, and if you have had house plants “vacationing” outdoors for the summer, I have a few tips to help them acclimate to their indoor location.
First, make sure there are not hitchhikers coming in with the plant. Insect pest populations are kept in check to a degree by outdoor weather and predator insects. That potential is eliminated indoors.
Three primary pests to eliminate are aphids, white flies and red spider mites. All three of these insects feed on the sap of plants, and each has their favorite location and host plant.
Aphids always feed on the most tender new growth, so they will be on the tips of the stems and often cause distorted-shaped leaves.
White fly larvae feed on the underside of the leaf and usually only the adult stage is noticeable as they fly around when the leaves are disturbed.
Red spider mites usually start their attack on the underside of new, tender growth, and the first symptom is yellow speckling leaf color followed by webbing in the leaf and branch crotch.
Amazingly, all three of these pests can be controlled using one insecticide called neem oil. It is an organic product so it is safe to use indoors, but I would rather that you take your plant outside so you can do a thorough spray application. That means spraying both upper and lower leaf surfaces and being thorough is imperative if you want to eliminate the pests before they become a major issue. If you see the insects or there is evidence of them, I recommend two applications 10 days apart.
Second factor is light. Outdoors, even in the shade, daylight floods the plant from all sides. Indoors, light comes through the window from just one side. Add to that the much shorter length of daylight hours and factor in how many cloudy days we have in winter. Not surprising that often there is little growth during winter months.
To help the plant get used to the light reduction, bring it in for a few days and then put it back outdoors when the weather permits for a few days. Do this for a couple of weeks and the plant will acclimate to its indoor environment without complaining.
When I say complaining, I am referring to the only way a plant has to tell you that it’s not happy and that means leaves turn yellow and fall off. The lower light means less energy for the plant, and with less energy, it cannot support the amount of foliage it has, so it aborts leaves in an effort to survive. It cannot change its location so it will do what it can do to survive in that location.
It depends on you to provide the best possible light indoors. Also, consider that plants that flower in the winter will have a higher light/energy requirement than foliage plants.
Third consideration is water. Much like us, when we work hard and are growing rapidly, we need more nourishment and water. As the growth rate slows or even approaches dormancy, the plant will use less water and most certainly less fertilizer. The indoor environment will have lower humidity, which also plays into how much water will be required.
I prefer a once-per-week water regimen. Then you know what day to do it and you’re less likely to stress the plant to the point of wilting or water-logged soil.
If the soil still feels moist after a week, cut back on the quantity of water you are using. If the soil is very dry, give it more water per application. Check repeatedly for a few weeks until you find the correct amount for that plant.
As to the use of plant food during winter, one application of water-soluble plant food per month will usually be adequate. If the plant roots are not using the fertilizer, it will build up as salt in the soil and can burn the roots.
