The greenhouse whitefly and sweet potato whitefly can be important pests. Generally, these insects confines their activity to the warmth of the greenhouse. However when outdoor temperatures become favorable, they leave the greenhouse to infest suitable hosts outdoors. Mining Insects Leafminers. The larvae of this group feed within the leaves of plants.
Females deposit eggs on the underside of leaves.
On hatching, the maggots burrow between the upper and lower leaf surfaces and feed. Many leaves may have light green or white winding trails that eventually turn brown and die. The mature larva emerges through a slit in the leaf surface and enters a resting stage where it passes as a pupa in the soil. There are many species and lifecycles may vary a bit. Susceptible plants include Chrysanthemum, Dahlia, Dianthus, Salvia, Verbena, Delphinium, Gypsophila and Aconitum.