How to Get Rid of Aphids & Whiteflies
Reduce Aphids and Whiteflies Using Integrated Pest Management (IPM)
Aphids are a common garden pest that can inhabit everything from fruit trees to small field flowers. Aphids are small, (about the size of a grain of rice) soft-bodied insects that use slender mouth parts to pierce various soft areas on a plant and suck out fluids. Aphids can come in many shapes and colors, but primarily feature a pear shaped body, long legs, and a tube like structure called a cornicle sticking out of their hind sides. Some Aphids are born with wings, which can improve their ability to infest a larger area in a shorter amount of time. Many plants have at least one or more species of aphid that is known to feed on it.
How do I know if I have an aphid or whitefly problem?
Whiteflies are small bodied, white insects with wings that may have spots and vary in size. Whitefly infestations can be very difficult to spot, and the primary indicator is typically a black, sooty mold as will be discussed later on. Whiteflies and aphids are very similar in terms of combatting their infestation and the potential damage they may cause to your garden.
Aphids tend to feed in groups but can be found individually in some cases. When checking for aphids, look for a flat square head and large oval shaped body. Be sure to check the undersides of leaves, as they have been known to hang out there. Aphids tend not to move, even when disturbed. This can be a key identifier when comparing to other insects, such as leaf hoppers.
The same goes for whiteflies, which tend to not be visible as they will hang our on the undersides of leaves until disturbed. Brushing and shaking plants, or watering or spraying them will typically cause whiteflies to be disturbed and they will rapidly rise from the plant until it is safe for them to return.
Aphids have a relatively quick reproductive cycle and reproduce asexually year-round. Females can give birth to up to 12 offspring a day without mating, and in warmer conditions, Aphids can mature from nymph to adult in just over a week’s time.
While aphids and whiteflies can cause damage to leaves and stems, and even stunt plant growth in new plants, there is a second danger that results from the byproduct of their feeding, which is the secretion of honeydew. Aphids and whiteflies rarely kill a mature plant, but infestations can lead to a problem with sooty, black mold because of the honeydew on the leaves. This mold is airborne, and spores land on the honeydew and can reproduce at a rapid rate, resulting in crop loss if left untreated. Additionally, this honeydew can attract ants, so if you see ants climbing up a tree near your crop, check it for aphids.
Luckily, aphids can be relatively easy to control. Here are some ways to use IPM to combat aphids and whiteflies
Check surrounding crops – if your surrounding area has plants or weeds, it may be a good idea to check for aphids on these plants, as they can lie in wait for crop plants to emerge. These can also play host to predators, so if you find things like ladybugs hanging around the area, you can leave them be.
Check your crops before transplanting.
Prune areas of plants affected by aphids early on if clustered.
Use slow-release nitrogen or carefully monitor nitrogen input, as more N favors aphid reproduction.
Reflective mulching techniques can also be used to repel invasive aphids.
Natural Predators – Be sure to monitor your area for predator species as you can, and take it as a good thing when you see predators such as ladybugs or parasitic wasps. Parasitic wasps use aphids as a primary host for their young.
Plant derived oils offer a safe alternative to traditional pesticides, and can still function just as well. In the even that an aphid infestation occurs, using horticultural plant oil blends such as Guard 'n Spray by Rhizoflora can eliminate them by suffocating the animal and slowly destroying its soft body. It is important to note that when contact-based solutions are applied, thorough coverage and daily application is necessary until the infestation has succumbed to the chemical control.