Thrips are small, narrow insects with fringed wings . Thrips survive on a wide variety of food sources, both plant and animal. They pierce and drain cells with specialize sucking mouth parts. The draining of hosts cells is what makes these creatures a problem for home gardeners because they leave dead and dying cells in their wake.
They can fly although not very well and more or less hop around plants. Strong winds can carry them quite far though.
Symptoms and Damage:
Thrips often leave tell tale signs of infestation in the form of silvery, whitish patches on leaf surfaces. Plants with delicate leaves are prone to discoloration and disfigurement but the most damage is done to flowers which will be destroyed by thrips. Upon close inspection the insect will be visible as brown specks on the leaf surface and can often been seen hopping/flying from leaf to leaf.
Habitat and Life Cycle:
Adult thrips can be found directly on the leave surface and will scatter when bothered. The larva emerge from eggs which are laid on the inside of the leaves and drop into the soil where it will cocoon itself until mature enough to make it back to the leaf surface. Their rate of development is proportional to the quality of their food source, high temperatures and dry conditions.
Control and Prevention of Thrips
There are many benefits to avoiding chemicals when dealing with insect invaders. The harsh chemicals in some insecticides may cause more harm to an already injured plant not to mention the possible harmful effects to you or your loved ones.
✔– First choices for attempting insect control.
✔– Used when green don't solve the issue.
✔– Only use when blue options have failed and the plant cannot be discarded.
Prevention✔- Keeping long grasses, weeds and decorative plants trimmed near windows that have your house plant in them and be sure the screen is in good condition, although thrips will fit though most window screening. An infestation can also occur from contaminated plants; this includes the soil, the leaves, the pot, the whole darn thing. ALWAYS inspect any plant you are considering giving a home.
Manual✔- Yellow sticky traps can be used to monitor and control thrips populations. Sometimes a population can be destroyed with a stiff spray of water or the plant can be submerged in water and gently swished back and forth.
Organic✔- Neem Oil Spray can be used by spraying both the top and bottom surfaces of leaves directly on the plant. Sabadilla is another botanical pesticide reported to work well for thrips. It is derived from the sabadilla lilly seed.
Biological✔- Thrips are difficult to control because of their small size and quick growth rate, it means an insect predator needs to be small enough to fit into the crevices that thrips hide in to feed. The most effective are reported to be Aphid wasps and Phytoseiid mites. Biological insecticide is another reported effective strategy against thrips, try things like Beauveria bassiana and Verticillium lecanii.
Chemical✔- Chemical pesticides made for thrips are very effective and inexpensive. Repeat applications will be needed to control all stages of the thrips life cycle.
More Information on Thrips