Houseplants provide natural beauty to the home, but may develop offensive odors due to disease or soil conditions. They have some special requirements to remain healthy. Because they are grown in an enclosed environment, they are completely dependent on the owner for care. Depending on the variety, houseplants need plenty of sunshine, adequate water and moist conditions to remain healthy. Healthy plants are less likely to develop offensive odors.
Using garden soil for houseplants creates problems, including poor drainage, weeds and odor. Garden soil has an aromatic smell that may be offensive in an enclosed, indoor setting. Instead, gardeners should grow houseplants in a sterile potting medium, according to the University of Missouri Extension Service.
Over watering leads to root rot, which creates to odors. Gardeners should water when the soil is slightly dry and only enough to moisten the soil. Water by placing the pot in a sink with 1/2 inch of water in the bottom instead of pouring water on the top of the plant. This approach promotes thorough, even watering, according to the University of Missouri Extension.
Diseases such as fungi or mold causes odor. Gardeners should repot any plants that show signs of mold or disease on the leaves or growing on the soil surface. Remove any diseased leaves and avoid over watering. Discard severely diseased plants. When using old pots, gardeners should wash them first in a diluted chlorine bleach solution to destroy any lingering diseases, according to Cornell University.
Pots with small drainage holes may not provide adequate drainage, promoting root rot and other diseases that cause odors. As plants grow, they need to be repotted to provide ample room for the roots. Yellowed or tightly coiled roots are a sign that the plant needs to be repotted.