Controlling Whiteflies in Your Garden
Whiteflies are among the most nuisance pests on the farm. Their appearance tends to resemble tiny, pure white moths; however, they are closely related to the sap-sucking aphids. When disturbed in any way they tend to fly away so quickly. If you are looking for them, you should look at the underside of leaves. That’s where they mainly hide and it makes it hard to control them.
They normally increase in number very fast and during summer, the whiteflies easily mature from egg stage to adult stage very fast. This makes them viable to laying eggs in a span of 16 days.
Affected plants: tomatoes, eggplants, peppers, sweet potatoes, plants from the cabbage family.
Injure plants by sucking the juice from them.
Cause Leaves to become yellow, shrivel and drop prematurely
Plant death if highly infested
Indirect Damage (adult whiteflies)
Transmit viruses from diseased to healthy plants
Excrete “honeydew” that forms a sticky coating; it is then colonized by sooty mold (making leaves look black and dirty).
Excessive sooty mold can prevent light from reaching the plant leading to stressing.
For sooty mold, you can easily wash it off with a forceful stream of water on the sturdy plants. The famous Argentine ants also tend to feed on the honeydew and may be beneficial to ensure the plants still thrive well. The adult whiteflies tend to lay eggs randomly in circles or arcs on the underside of the leaf. Thus, you need to look even under the leaves when you sense infestation.
There are various methods to use to reduce instances of whitefly:
First, you need to get familiar with certain natural enemies of whiteflies and this will help you while checking the farm. This includes the tiny parasitic wasps that lay their eggs inside the bodies of the whiteflies. You can also attract natural enemies like small birds to the garden which can help reduce the number of whiteflies.
Other natural enemies: ladybugs, dragonflies, spiders, lacewing larvae, hummingbirds.
Also, whenever you buy new plants, be sure to check if the plants are infected. Always examine your new stock, because if the previous stock was affected, the new one will also be affected. This needs a full examination of the new stock to ensure healthy plants come from it preferably for about 1-2weeks. This gives the large nymph time to have already developed.
Also, prune away severely infested potions of the plants and dispose of the materials completely. This should be according to the recommendation given by your area extension officer. You can also use insecticidal soaps to kills harmful whiteflies while sparing the beneficial insects. Horticultural sprays can also come in handy to help in the control of the whiteflies.
Early in the morning, always check the back of the leaves for eggs and see if any flies fly away from there. You can also start by blasting the insects using a watering hose, you may also spray your leaves with insecticidal soap. The temperatures need to be cool as hot temperatures may cause a reaction in the plants.
You can also hang sticky traps above the plants at the beginning of the planning season to detect invasion early.
Proper sanitation should also be maintained by removing weeds, and plant residues around the plants that may pose a threat.
Also ensure that at times, the field is free from any crops to give the land time to rejuvenate and also give the soil time to replenish and be better for the next planting season. Even a week at warm temperatures without any kind of temperatures can be sufficient to help remove potential whiteflies, to reduce invasion.
You can use a hand lens to check the underside of the younger leaves. Regular screening is also recommended to ensure that they are detected easily. This applies to the plants in the greenhouse, as the whiteflies can easily enter when there are open doors or windows for better ventilation.
You may also decide to vacuum whiteflies in the morning when the insects are cold and dull as this helps remove the adult whiteflies to prevent them from laying more eggs. Vacuuming can easily help to get rid of nymphs and larvae.
Use slow-release fertilizers that will help maintain healthy plant growth. You need to prune the farm moderately as it easily stimulates whitefly growth.
The full life cycle of the whitefly often lasts for between 15-40days, which highly depends on the environmental conditions which allow eggs to easily turn to adults due to the temperature. The eggs normally stick on the underside of the leaves by the use of a pedicel. The nymph also develops in different stages and continues feeding at the same place until they reach the adult stage.
They tend to be white due to a layer of white powder that covers both the bodies and two pairs of wings. The two species of whiteflies include the tobacco whitefly and greenhouse whitefly.
Image courtesy: greenmylife