Potted flowers aren't immune to critters that attack garden plants. Even indoor plants can suffer from pest problems. Identifying those pests provides the necessary information for controlling and eradicating problems. Check the plants at least once a month for pests so that any issues can be dealt with before irreparable damage occurs to the flowers.
Aphids, mites, scale and whiteflies attack indoor and outdoor plants. Symptoms include discoloured blotches on the leaves, holes or ragged edges, and a sticky residue called honeydew on the leaf surface. Aphids and mites typically colonise and feed on the undersides of leaves. Mites leave webbing on the plant, especially when a large population is present. The larval form of the whitefly feeds on the undersides of leaves causing damage. They look similar to scales, which resemble a brown growth on the plant. Scale insects do not resemble insects because they don't move and have no visible legs.
Some pests live in the soil and feed on the roots and stem base or they emerge from the soil only briefly to feed on foliage. Black or dark-brown sowbugs roll up when touched. They live within the soil or under dead plant matter, emerging only at night to feed. The multi-legged millipede dwells under the pot or in the soil where it feeds on the roots or bulb of the plant. Ants may invade outdoor flower pots. Though they typically feed only on the honeydew produced by other insects, such as that of aphids, they also may feed on seeds or seedlings.
The best control method for insect pests in flower pots depends on the type of insect. Soft-bodied insects such as aphids are destroyed by the use of insecticidal soap. A sharp spray of water can wash away mites, aphids and other foliage dwelling pests. Insecticides formulated for the specific pest also destroy potted plant pests. Re-potting into fresh, pest-free soil is an option. Submerging the pot in water while keeping the foliage above the water surface also drives out soil pests. Drain the pot thoroughly after submerging so the roots don't drown or rot.
Preventing pests eliminates most concerns in potted plants. Treat outdoor pots for aphids and other common pests before bringing them indoors for winter, otherwise the plants can transfer pests to other indoor plants. Quarantine new plants in an area away from other plants for a few weeks to ensure the new plants aren't bringing pests into the home. Aphids, one of the more common pests on indoor and outdoor flowers, attract ants. Controlling aphid population prevents ant infestations. Keep your flower pots clean by removing and disposing of dead and fallen plant material. These materials provide nesting material for pests.