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There are a number of indoor plant pests that frequent greenhouse grown houseplants, but rarely appear on plants in the home but can find their way indoors.
Thrips cause silvering of foliage, distortion and streaking or spotting of bloom. Black vine weevils or rose beetles feed at night, notching leaves in from the margin.

The fern caterpillar also feeds at night. Slugs and sowbugs congregate under moist pots.

Springtails are small, wingless jumping creatures that come into the house in soil rich in organic matter (decaying wood chips for example).

They are not very harmful, but aggravating. Sometimes manure in the potting mixture brings in maggots which develop into small black flies that are more annoying than injurious.

Bulbs – Lurking Inside

If narcissus or amaryllis bulbs rot, a large, yellow-white maggot may be inside, the larva of the narcissus bulb fly. New bulbs purchased for forcing should be free of greenhouse pests, but sometimes amaryllis summered outdoors are invaded.

It may be necessary to screen the plants to keep the flies from laying eggs or to leave them indoors.

Diseases caused by bacteria or fungi are not common on house plants, because there is seldom enough moisture for infection. A few leaf spots may show up on aspidistra or rubber plant; if they are sufficiently unsightly, remove affected leaves.

Primroses and geraniums started in greenhouses sometimes have the familiar gray mold of Botrytis blight, but this will disappear in a dry room.

More important are diseases caused by unfavorable environmental conditions. If leaves turn yellow and drop or if swellings (oedema) appear in geranium or begonia foliage it may come from over-watering, especially in cloudy weather.

Yellow ring spots on African violet leaves are due to using water colder than room temperature. Scalded areas in foliage come from sudden exposure to sun. Stems rot where they touch the pot due to accumulation of salts on the rim.

My Pesticide Preference

Personally, I use Neem oil pesticide / insecticide / fungicide first before using any man-made chemicals. Neem is natural, organic and safe, plus you can find it at Lowe’s and Home Depot.