Fresh air and long days are just two of the many joys of summer. Because of them, many gardeners like to move their houseplants outdoors during the summer months. However, now that the temperatures are beginning to fall and the days are getting shorter, it is time to move them back indoors for a long winter rest. Here are some tips to help you and your plants make the transition to their new winter home:
Houseplants growing outdoors are accustomed to receiving more sunlight than they do indoors. Research has revealed that tropical plants grown under high light conditions produce "sun leaves," while those grown under low light conditions have "shade leaves." These leaf types differ structurally in that sun leaves have less chlorophyll (the substance that plants use to convert sunlight to energy) and the chlorophyll that is present is located deeper inside the leaf. Sun leaves also tend to be thick, small and numerous, while shade leaves are thinner, larger and fewer in number.
When plants are moved from one light condition to another, they need time to adjust. If they are forced to change too quickly, they will drop their sun leaves and produce new shade leaves, a lengthy, stressful process. If the conversion conditions are less extreme, the plant can transform sun leaves into shade leaves, a natural, less-stressful process.
To help our houseplants acclimate to the lower light levels found indoors, place them in an area of the home that receives plenty of light, then gradually move them to their permanent, darker location. This shift can take four to eight weeks to complete. During this time, do not be alarmed if a few leaves turn yellow and drop off. This is natural as the plant is trying to balance itself in the new growing environment.
Also shifting in the plant is the need for water and nutrients. Plants growing outside need more of both when light levels are high and days are long. That need decreases as the days shorten. When light is limited, the need for water and nutrients decreases dramatically. During the winter months, it becomes easy to overwater and overfertilize plants. Excess water and fertilizer can kill a plant by damaging the root system. Overwatering can suffocate roots by eliminating oxygen, and excess fertilizer can burn roots.
It is never wise to water on a set schedule. Rather, allow the potting soil to tell you when watering is needed. Check to see if the soil is moist 1-inch deep by inserting your finger into the potting mix. Don't water unless the mix is dry.
Another common mistake is fertilizing during the winter in order to perk plants up. This is the exact opposite of what should be done. Remember it is a lack of light that gives plants the doldrums; not a lack of fertilizer. Therefore, it is best not to fertilize at all during the middle of winter (December-January) and to fertilize sparingly during November and February, maybe one-fourth of the normal rate.