Houseplants bring nature indoors and can add vibrant color and life to your home. Yellowing of the plants' foliage can detract from your collection's appearance, but the problem is about more than just aesthetics. Yellowing leaves often point to a management problem that, if left untreated, may lead to a weak or dead houseplant.
Insufficient sunlight may cause yellowing of the foliage, according to Purdue University. All houseplants have varying lighting needs. Consult the nursery or garden store that initially sold you the plant or seeds, and appropriately adjust the plant's position near a window to give it the amount of light it needs. Some might need to be closer to the window for more light, but remember, too much sunlight is also bad, and plants exposed to more sun than they need may become scorched.
Yellowing of the leaves, combined with slow or stunted foliage growth, may be a symptom of poor soil nutrient levels. Use a general 10-8-7 fertilizer labeled for use on houseplants, according to the University of Connecticut. For the best results, the university recommends fertilizing March through October, when houseplants typically experience their peak growth. Follow the fertilizer's labeled guidelines since potency varies by product.
Raising houseplants in pots that are too small to for the plants' growing roots may create yellow leaves since the roots can't expand to absorb adequate amounts of nutrients or water. Likewise, houseplants grown in poor quality soil may also turn yellow, according to Ohio State University. Repot the plant in a larger pot and use commercially prepared potting soil.
An infestation of pests on your indoor plants, like thrips or aphids, can stress plants and cause yellowing. Treat the plants with a standard insecticidal soap or a pesticide labeled for use on indoor plants. While treating a plant, separate it from other houseplants to help keep the pests from spreading.