10 Tips for Preparing Plants for Wintering Indoors
Does Moving a Plant Inside or Outside Cause Stress?
Although I love the advent of autumn with its cool temperatures, brilliant leaf colors, crystal blue skies, and harvest festivals, I am never completely mentally ready to let the summer go. For me, nothing signifies the end of summer more than moving my indoor plants from their outdoor summer homes into the house for the winter.
It seems like a redundancy, bringing houseplants indoors, but many of us in temperate zones spend summer with at least some of our indoor plants outdoors to give them a growth burst or to enhance outdoor living areas. Taking houseplants outside also gives us an opportunity to clean hidden indoor spaces and give our homes a fresh, uncluttered summer look. It's a pleasant change.
But as the time to bring houseplants indoors approaches, we need to prepare them and their indoor environment for healthy winter living by lessening the stress that can be caused by the forced migration we impose.
10 Tips for Preparing Indoor Houseplants for Healthy Winter Living
- Start by taking a micro-environment assessment of the temperature fluctuations in your house. You want to keep plants away from direct cold drafts and hot air vents. You may have to rearrange furniture or acquire tall plant stands and wall or ceiling plant hangers to keep plants away from hot and cold extremes.
- Prepare to mimic the relative light conditions the plants grew in during the summer. For example, spider plants and Christmas cactus will do better in brighter conditions than those tolerated by low-light lovers like schefflera. Choose a window with a southern exposure for plants that do well in brighter conditions or a window with a northern exposure for those that can do well at lower light levels.
- If you have pets who like plants, and many do, prepare for putting the plants where pets can’t get at them. Not only don’t you want your plants damaged by curious paws and mouths, you also don’t want your plants to harm your pets. As a precaution, refresh your knowledge of household plants known to be toxic to pets.
- Keep the plants in the containers they lived in while outdoors. This is not the time to disturb their roots, which would encourage new growth.
- Inspect the leaves, stems, and soil for plant pests and other insects. Remove them by hand or use an organic houseplant insecticidal soap safe for humans and pets. (If you decide to use an insecticidal soap, apply it after the final shower and air drying. See Tip 10 below.) Over the years, I have found some rather fascinating creatures making themselves at home with the houseplants that have summered outdoors. Among them were spiders, ants, earthworms, and wasps.
- Cut away any dead or damaged leaves and stems, disinfecting your cutting tools, with household bleach followed by a clean water rinse, from one plant to another to avoid infecting a healthy plant. Remove all dead and rotting plant material from the surface of the soil.
- Refrain from pruning away healthy leaves and stems. Heavy pruning will encourage new growth, just as repotting. Remember that we want the plants to rest, not to embark on a growth spurt.
- Scrub the outside of the pots thoroughly with a steel wool pad or nylon scouring pad dipped in a mild soap and water solution to remove dirt and mold. Steel wool works well for plain terra cotta pots. For glazed, painted, and plastic pots, stick to a nylon scouring pad to avoid damaging the pot’s finish. If a mold infestation is particularly bad on a plain terra cotta pot, you can add one part household bleach to ten parts of the mild soap and water solution. Just make sure you keep the bleach well away from any of the plant tissue.
- Take the time with larger-leaved plants, such as schefflera and rubber plants, to wipe each leaf clean, top and bottom, with a cotton swab and plain water. Summer dust and pollen remaining on the leaves will further diminish the limited indoor light and prevent the plant from absorbing whatever moisture is in the dry indoor air.
- Finally, shower each plant thoroughly using a garden hose with a mist or shower attachment. Get underneath the leaves, too. Then let the plants and pots air dry outdoors before bringing them in for their winter rest.
Why Houseplants Brought Indoors for the Winter Are Susceptible to Plant Stress
While houseplants have been outdoors for the summer, they've acclimated over several months to certain light, humidity, and temperature conditions. Chances are they’ve received more light and have enjoyed higher humidity than they did indoors. They have also adapted to temperatures that may have been fluctuating as many as 20 degrees between day and night. Having been watered and fed frequently, they have enjoyed a healthy growth spurt, even as the days began to shorten and the weather to cool at the end of the summer season.
Now, as we bring houseplants indoors, we will be changing their environment drastically in a very short time. They will be experiencing much less light and humidity than they did outdoors, as well as a much smaller fluctuation in day and night temperatures, and we will be reducing the water and plant food they had become accustomed to. In essence, we will be asking them to stop growing and start resting. It’s like asking a speeding freight train to stop on a dime.
Despite our best efforts, most houseplants transitioning from the outdoors to the indoors will show, to some degree, stress signs that include yellowing, wilting, parching, or dropping leaves. If the stress is too great, the plants will die. Here are 10 tips for making the transition from a summer outdoors to a winter indoors as stress-free as possible.
Know Your Average First Frost Date
You need to know the average first frost date for your area so that you can migrate your plants from outdoors to indoors before they are damaged or killed. Use Dave’s Garden zip code locator to find the first and last frost dates for your area. Then allow plenty of time to rearrange your house, clean the plants and pots, and bring the houseplants indoors before that date arrives.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.