Unfortunately, your plants have spider mites. The bugs are tiny-almost too small to see with the naked eye, although if you examine the webs carefully, you will see the spiderlike mites moving about within them. Most often, gardeners learn they have the pest when they spot the webs-and by then the infestation definitely has the upper hand. Spider mites are difficult to eradicate, especially on plants inside the house. Attack these pests by using several techniques. First, wash the plants with a soapy solution of mild dish detergent or insecticidal soap. A forceful water spray in the shower will help, too. Remove all webs, wiping upper and lower leaf surfaces. If necessary, follow this treatment by applying a pesticide designed to kill spider mites. Make follow-up applications. Isolate these plants from noninfested plants in your home. Mites multiply in hot, dry air. Increase the humidity inside your home with a humidifier. In spring, when nighttime temperatures are reliably above 55 F, take the infested plants outside. Increased air circulation will help eliminate the pest.