Aphids are small insects (1/16 to 1/8 inch long) that can be spotted with the naked eye. They are six legged, can range in colors from white, red, gray, green, yellow, black or even pink, and they can be found with or without wings. These pests have a sucker mouth that they use to pierce plant tissue and feed on the plant juices. Heavy infestations may kill or severely damage a plant, and aphids can multiply quickly under the right conditions. The honeydew that the aphids excrete leave leaf surfaces sticky, shiny, and provides a food source for sooty mold and ants. This honeydew should be wiped off since it blocks light needed for photosynthesis.
It is almost impossible to prevent aphids in an outdoors garden. You may control it with chemical or non-chemical methods. Aphids in your indoor garden is best prevented by not introducing them into the environment. Do not walk through an outdoor garden then into your home without checking yourself for bugs and washing your hands. Check the undersides of your leaves and portions of new growth for aphids.
Defeating with Sprays:
Aphids can easily be defeated with insecticidal soaps and pyrethrum sprays. Both are applied in the same manner. Mix according to product usage label, then apply liberally to the foliage of the plants on all infested areas. This MUST be repeated in 5-10 days to kill newly hatched eggs and remaining adults. A third treatment 5-10 days later is also recommended to kill any survivors.
Also see our Natural Remedy Section
Lacewings and lady bugs are the two most common insects used to control infestations. Lacewings are the most menacing to aphids. Release approximately 1-10 per plant to clear or minimize an infestation. Adult lacewings are preferred over larvae because larvae take time to grow.
Lady bugs are another excellent predator. Most nurseries will supply them during the summer. Lady bugs in a garden are best when released 5-20 per plant each 1-2 weeks till the problem is minimized. However, lady bugs in a greenhouse are not so effective. If HID lamps are being used, about half of the released lady bugs will fly towards the lamps and *pop! They should then be released at a rate of about 50 per infected plant in a greenhouse.
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