Successfully growing houseplants starts with understanding their needs. Primary among these is light. Light is the energy plants use to create their food. You cannot grow a plant where there is not enough light, no matter how good it looks in the location.
Often purchased on impulse, plants need to be planned to bring about more consistently successful results when it comes to growing them indoors. Walk through your home and think about where plants would be appropriate. Focus particularly on areas where the family spends a lot of time, such as the kitchen or living room. Where is sufficient light? How many and how large should the plants be? Will they sit on a windowsill or on the floor, or perhaps hang in a basket?
Houseplants are available from a wide variety of sources, but wherever you purchase them pay attention to quality. Always purchase plants that are vigorous and healthy and have an attractive shape with no insects or diseases. Look at the foliage carefully. Avoid plants with yellow leaves, brown leaf edges or spots that indicate the plant has been poorly cared for. Look for signs of scale, mealybugs or mites that could infest your other plants at home.
Choose a plant that will survive in the location where you intend to place it – particularly regarding the amount of light the spot receives. Different types of houseplants will grow in higher or lower light conditions. Ask the nursery staff to help with the selection or check references on growing plants indoors before you make your final decisions.
When you purchase a plant, make sure the pot has a tag with the name of the plant on it, especially if this is a spur of the moment purchase of a plant you are not familiar with. Without a name, you cannot look up or ask someone for information about the plant.
Houseplants are generally grouped into high light, medium light and low light categories. High light levels are provided by unobstructed east-, southeast-, southwest- and west-facing windows. Medium (summer) to high (winter) light levels come through unobstructed south-facing windows. North-facing windows provide low light levels. Low light levels may also be provided by placing plants several feet away from east-, west- or south-facing windows. Light is most often provided by sunlight shining through windows, but artificial light can also be effectively used to grow indoor plants.
Place plants where you have determined they will get the proper amount of light. Rarely do you have to worry about indoor plants receiving too much light.
Within four to eight weeks a plant will indicate if there is a problem with light. Whether there is actually enough light in that spot is, after all, the plant’s decision – not yours. If there are no pests present and the plant has been watered properly, a deteriorating condition usually indicates insufficient light. Move the plant to a brighter location.
People are always obsessing over how to water their houseplants. For the majority of plants it’s really quite simple. Stick your finger into the pot. If the soil feels wet or moist, don’t water. If the soil feels dry, water. Do not allow plants to wilt before you water them. This stresses them and can cause leaf drop, flower bud drop and brown leaf edges.
Apply water until some runs out of the pot’s drainage holes and into the saucer underneath. That way you know that you have moistened the entire root ball. Do not let the pot sit in a saucer full of water, however. Remove the water in the saucer if it is still there a few hours later. You can use a kitchen baster to suck the water out of the saucer if the plant is too large to dump the water out of the saucer. There, isn’t that simple?
Houseplant containers should definitely have drainage holes. There must be some way for excess water to drain out of the soil when we water. Otherwise, we run the risk of the soil staying saturated, drowning the roots and encouraging root rot. Choose pots you find attractive and fit in well with your interior decor. Clay, plastic, ceramic or other materials are all appropriate as long as they drain.
Only use soils or mixes specifically blended for container use called “potting soil” or “potting mix.” Do not use topsoil or garden soil products or soil you dig up from your outdoor garden beds. Professionals use soilless potting mixes made up of peat moss, perlite and vermiculite because they work so well. You must, however, regularly fertilize plants growing in them. Make sure whatever potting soil or mix you use is loose, drains freely and does not pack tightly in the pot.
Since virtually all of the plants grown as houseplants are native to the tropics, they should not be exposed to freezing temperatures. Also avoid extremely high temperatures, as in leaving plants in a parked car in summer with the windows rolled up. The normal temperatures we maintain inside our homes are just fine for most houseplants.
If you have a houseplant that has not been doing well indoors, try moving it outside to a shady location for the rest of the summer. Given good care and time, you will see the plant rejuvenated. Then, you can bring it back inside and try it in a different location when it looks better.
Dan Gill is a horticulturist with the LSU AgCenter. He can be reached at DGill@agcenter.lsu.edu