Definition of Houseplants
There is no such thing as a houseplant. Why make such a statement? Well, because no plants are native to a home. Plants we use indoors are native to various environments including deserts and jungles. So how do we make a houseplant feel at home?
We choose plants that will tolerate our indoor environments so we can pot them up and decorate the interior of our home. Most of these plants are from tropical regions where they grow beneath a dense tall canopy of trees. Thus, they can tolerate lower light levels which are typical of most home settings.
Adequate Light the Key to Success with Houseplants
The typical indoor environment has very low light intensity. House plants differ significantly in their light needs. A plant in less than sufficient light will gradually go downhill. Under minimally sufficient light it will survive but not grow very much. In winter, light levels are even lower adding to the stress on plants.
Placing a plant in the higher light intensity of a shady outdoor location for the summer can help rejuvenate it and allow it to build up its reserves, enabling it to withstand a subsequent period indoors. Grow lights can help if you have room for both plant and lamp.
Fluctuations in light intensity can severely stress plants. The tissues of a plant change to adjust to the light intensity of their environment. A plant grown in low light will be much more efficient and sensitive to light than the same species grown in high intensity light. If you move a plant growing in low light next to the plant in the high light environment, it will sunburn or scorch while the same species grown in high light will not be affected.
Moving plants from high to low light will result either in gradual decline, or in the case of some plants like Ficus, sudden leaf drop. These factors are important to remember when bringing your plants indoors for the winter. It’s best to gradually acclimatize them to the indoor environment over a period of a week or two. Start by bringing them in for a few hours a day, increasing the time slowly over a two-week period. Larger plants can be first moved to an outside location with very low light intensity for a couple of weeks and then into the house.
Temperatures inside your house can vary widely. Flowering potted plants do best in temperatures of 65 to 75 degrees F during the day and 55 to 60 degrees F at night. To extend the bloom of flowering potted plants in the home, move them to a cool spot at night. Foliage plants are more tolerant of high temperatures, but they thrive at temperatures between 65 and 70 degrees F.
Soil Moisture and Humidity
In addition to adequate light levels, a second key to keeping plants healthy indoors is proper soil moisture. Dry soil brings obvious problems, yet more houseplants are damaged or killed by overwatering than perhaps any other factor. When the potting soil stays soggy wet, roots lack oxygen and die. Most plants should be watered thoroughly and not watered again until the growing mix has begun to dry out. Some such as African violets do well in a continually moist, but not wet, growing mix. Wicks draw water up from a reservoir underneath the plant to provide a gradual, constant supply and eliminate the need for frequent watering.
The air in a house typically has low humidity, even here in Central Texas. Some houseplants benefit from measures to increase the humidity around them. Terrariums, placing gravel trays filled with water among the plants, and grouping plants together are ways of creating a humid environment. Temperature fluctuations are also stressful to plants. Remember there are not heating or air conditioning vents in the rain forest! These drafts can result in more stress and damage. Avoid placing plants under vents and near entry or exit doors.
Frequency and amount of fertilizer application will vary depending on the age and rate of growth for each plant. As a general rule, use a recommended fertilizer every 2 weeks from March to September. During the winter months no fertilizer need be added at all because reduced light and temperature result in reduced growth. Fertilizing at this time could be detrimental to some house plants.
When applying fertilizer in a solution, make sure that some runs out of the bottom of the pot. This prevents root burn and the buildup of soluble salts or excess fertilizer and reduces the chance of burning the plant. If applying fertilizer granules, be sure to water them in well. Granules need time to break down and become soluble, so in general, they are only applied monthly.
Remember that plants do not grow as vigorously in winter – even in the house, due to lower light intensity. As a result, they need less water and fertilizer than in the summer months. Avoid the temptation to try to fertilize them into vigorous growth because it will create more problems like root rots and salt damage.
Some plants tolerate less light than others. They also vary in the amount of humidity they prefer as well as the temperature range they tolerate. Check out the link below to help you choose plants that will thrive in various areas of your home and help you provide the proper care necessary to keep them healthy and happy.
Caring For Houseplants – University of Missouri Extension
Growing Indoor Plants with Success – University of Georgia Extension