Houseplants are a necessity for gardeners in cool climates. We get desperate for greenery between November and April-and sometimes longer! If I can't schedule a tropical vacation, I buy a tropical houseplant to help me weather the winter and reduce the symptoms of spring fever. My latest favorite is Dieffenbachia, commonly known as dumb cane. It not only alleviates that aforementioned fever, but cleans the air remarkably well.
I recently purchased Dieffenbachia amoena. This particular species is the largest of the bunch, growing 5 or 6 feet tall and brightening a drab corner of my living room. The giant leaves measure about 18 inches long and 12 inches across. It seems happy growing near my east-facing window, but convincing it to grow as lovely in Idaho as it would in its native Central American climate might be tricky.
Most common houseplants thrive in humid and warm conditions with filtered sunlight. This makes sense, because most hail from the tropics. While in Central America recently, I saw huge philodendrons scrambling up tree trunks. The leaves closest to the light were as big as a man's chest. These "houseplants" must be sorely disappointed to call our houses home. However, we can do a few things to make them happier.
Care and Feeding
Most books recommend misting these houseplants regularly to raise the humidity, while others suggest putting a pan of gravel filled with water under the plants so that the evaporation will elevate the humidity. With our extremely hard water, neither is a good option. The mineral deposits can harm the leaves and roots. Instead, I put a humidifier or cool-air vaporizer near the plants. They love the moist air.
Allow Dieffenbachia's soil to dry out between waterings, and fertilize every 2 weeks during the warmer months. It also prefers to be a little pot bound.
NASA tests confirm that plants clean formaldehyde and other toxins from the air. We have formaldehyde in our homes from paper towels, garbage bags, tissues, carpet backing, and floor coverings. Dieffenbachia removes not only formaldehyde, but also xylene and toluene - two other pollutants. Plus, their big green leaves help me make it through the long, leafless winter!
Photo by former managing editor Cathy Walworth/National Gardening Association