Night Blooming Jasmine & Aphids

Description

• Aphids often feed in dense groups on ornamental plants. More than 4,000 species of aphids exist, but the type that generally attacks jasmine are soft-bodied and pear-shaped. The insects are small and vary in color by species. It is normally unnecessary to identify the aphid species; control of aphids is the same for all soft-bodied types. Many aphids stay in one place, feeding and constructing waxy, shield-like structures over themselves.

Symptoms

• Aphids cause yellow spots on foliage, leaf curling and stunted or deformed leaves and flowers. The insects often cluster most densely on stems and buds. Low populations rarely do much damage to night-blooming jasmine. Large infestations interfere with proper growth and flowering and can transmit viruses.

Non-Chemical Controls

• Parasitic wasps lay their eggs in aphid bodies, and the feeding young turn the aphid into a dried-out mummy. If the aphids on your jasmine are mummified, wait one to two weeks to see whether the wasps finish off the aphids for you. Lady beetles, lacewings and other beneficial insects feed on aphids. Give them time to work before using pesticides that will kill these insects along with the aphids.
  Try spraying the jasmine with water from the garden hose. A hard spray knocks off many aphids, which are unable to return to the plant. Repeat every few days until the aphids are gone. This method has the added advantage of washing off the honeydew aphids excrete. Honeydew attracts ants and is a fertile growing medium for sooty mold.
  Remove weeds, especially mustard and sow thistle, which harbor aphids. Destroy the unwanted vegetation away from the garden to avoid accidentally giving aphids a ride to the jasmine. Use a urea-based, time-release fertilizer. Aphids thrive in the nitrogen-rich environments produced by high-nitrogen fertilizers.

Chemical Controls

• Some of the least hazardous controls are insecticidal sprays made with Neem oil or diluted soap, detergents or oils. The products smother the aphids or disrupt their cellular structure, killing them. Commercial insecticidal soaps containing other insect-killing ingredients are readily available and may be less harmful to the plant than homemade soap-and-water formulas. These products usually do not harm lady beetles or lacewings. To avoid phytotoxicity injury to the jasmine, rinse the insecticidal or homemade soap mixture off the plant a few hours after application.
  Foliar sprays made with malathion, permethrin or acephate kill aphids and their natural enemies and should be a last resort. Acephate works systemically and can kill hidden aphids.