Check the foliage regularly for aphids and thrips, tiny insects that sometimes feed on Million Bells' leaf sap. Flat, pear-shaped aphids colonize stems and leaf undersides. The yellow, red, brown, black or green pests secrete a clear, sticky waste called honeydew. Fringed-winged, white, yellow or black thrips hide in buds and furled leaves. A strong spray of water blasts the pests from the plants.