By now, our outdoor gardens are under a blanket of snow, so we turn our attention to our indoor gardens and caring for such plants as holiday cacti, cyclamen, poinsettia, orchids, succulents, cacti, foliage plants, etc. Based on questions we receive on our weekly WCCO Smart Gardens radio show, people over care for their houseplants - over water, over fertilize - or under care for their plants essentially ignoring them until they are dusty, dry and drab looking. So how does the houseplant owner balance good care with not overdoing it? Extension has good information on some of our favorite indoor plants, but here are a few tips to help.
Understand your plant’s growing needs
It’s always interesting to remember that somewhere in the world, my houseplants are indigenous and grow untended. Take African violets (Saintpaulia ionantha). As indoor plants, they are considered a bit delicate and fussy yet the native parents of these little fuzzy hybrids we enjoy were found growing from shady, mossy rock crevices in the Tanga region of Tanzania. Located near the equator, air temperatures range from 65 to 85 degrees F., there is plentiful rain, and day length is consistent. Knowing this helps me understand that my African violets will benefit from well-drained soil (the rocky crevices), indirect light (shady moss), and lots of water and humidity.
Examine plants, scout for insect pests
Mealybugs. Aphids. Scale. Ugh, ugh and ugh. Insect pests on houseplants can be hard, but not impossible, to get rid of. These insects have natural predators like ladybugs, praying mantis, and parasitic wasps outdoors. Indoors, it’s up to us as plant parents to scout for and manage these common insect pests.
- Good sanitation:
- Repot plants in fresh potting media
- Clean off containers and saucers, even trivets used to protect your table top.
- Remove plant dead flowers, leaves, etc. from the soil surface.
- Wash plants with water about once a month (large plants go in the shower, small ones in the sink) to clean up dusty leaves.
- Regularly (weekly) examine plants up close. A hand lens and a small LED flashlight really help to show off insect pests.
- Hand-pick insects if possible.
- Treat as necessary with low-impact products like insecticidal soap, horticultural oil and neem oil. They are available in ready-to-use sprays. These are contact pesticides and thus must come in contact with the pest. Follow all the instructions on the label. Use in a well-ventilated area.
A good resource from Extension: Managing insects on indoor plants.
Water: More is not better
The key to watering houseplants is to feel your plant’s soil (or bark or peat - whatever it is planted in) before watering and to make sure the pot is draining well. Root rot is a common cause of houseplant failure. It occurs when plant roots are constantly wet, when a container doesn’t drain well, and when a plant is overwatered.
Along with yellow leaves and leaf and bud drop, a plant that is suffering from root rot looks wilted. People will often mistake this wilting for wilting due to dryness. As the plant roots die in the saturated soil or bark, the plant cannot take up water to hydrate the rest of the plant and results in a wilted plant and, ultimately, a dead plant.
Suspect you have some root rot happening? Repot your plant in fresh, new potting soil or bark. While the plant is out of the pot, examine the roots and snip off any that are dark or mushy. Once repotted, hopefully your plant will have enough roots to take up nutrients and water from the soil and grow some new roots. Watch this video on Caring for your houseplants - Watering.