Monday, January 11, 2021

Spider mites on my houseplants – yuck! by Vicky Spelman

 

Close-up of spider mites
University of Maryland Extension

How are your houseplants doing?  See any webbing or discolored leaves?  You might have spider mites.  

Spider mites are tiny eight-legged arthropods that are related to spiders and ticks. 

~ they do not have antennae or wings – they get from place to place by crawling 

~ they can be problem all year indoors and have a very broad host range, but ivy and Norfolk Island pine seem particularly susceptible.

~ they are about the size of a period (.)

~ use a short, sharp beak to puncture the plant to suck the chlorophyll from the leaves

~ examination of infested foliage could reveal fine webbing 

Heavy mite infestation with webbing
University of Maryland Extension


Management:

~ if mites become a problem, periodically wash them down your houseplants with a strong spray of water, taking care to get coverage on the lower leaf surfaces

~ when control is needed, use insecticidal soaps for houseplants or one that is labeled for spider mites and houseplants

~ read and follow label directions

~ these sprays have no residual activity and only control mites and insects that are contacted directly and repeated applications will be needed

~ continue to keep plants watered and fertilized to promote health

“Control on house plants can be particularly frustrating. There generally are no biological controls and few effective chemical controls (primarily soaps and horticultural oils). When attempting control, treat all susceptible house plants at the same time. Trim, bag and remove heavily infested leaves and discard severely infested plants. Periodically hose small plants in the sink or shower. Wipe leaves off larger plants with a soft, damp cloth. Reapply these treatments at one- to two-week intervals as long as populations persist”. – CSU Extension

Additional resources:  University of Maryland, Iowa State University Extension, Iowa State Univ Extension2