Released: Oct. 1, 2020
Whitefly got ya? Check houseplants for tiny insect
K-State horticulture expert reports increase of whiteflies in Kansas
MANHATTAN, Kan. – A miniscule insect showing up in some areas of Kansas recently is doing its best to create a giant headache for homeowners.
Whiteflies are soft-bodied, winged insects closely related to the aphid and mealybugs. They can be as small as one-twelfth of an inch, are triangular in shape and are found on the undersides of leaves – often times on houseplants brought in from the outdoors.
Despite their name, whiteflies are not a type of fly, though they do have wings and are capable of flying.
“We have had reports of whitefly problems in various areas of the state,” said Ward Upham, a horticulture expert with K-State Research and Extension.
Recently, Upham urged homeowners to begin bringing houseplants indoors. Those that waited a little bit longer may not have to think twice about the whiteflies since they don’t do well in colder temperatures and will likely die within the week.
But those who have recently brought houseplants into the home should take a closer look at the undersides of the leaves to make sure they are clear of what appears to be white blotches – which is actually several whiteflies built up on the leaf.
“In such cases,” Upham said, “try applying insecticidal soap, neem-based products, pyrethrin, or Ortho Rose and Flower Insect Killer.” Neem oil is a naturally occurring pesticide found in the seeds from neem trees.
Whiteflies will not survive as Kansas’ outdoor temperatures turn colder, he said.
Turf Talk
Cold weather in Kansas also signals homeowners’ need to make final preparations for their lawn.
A common question Upham gets is whether to let the grass grow tall in the fall.
“Their reasoning is that the extra foliage will insulate the crown of the plant from the extreme cold of winter,” he said. “Although this may sound reasonable, in practice it probably does little to increase winter hardiness.”
Actually, Upham notes, a canopy that is too high during the winter may lay over and become matted down, leading to an increased incidence of winter diseases, such as snow mold.
“The lawn will benefit more from continuing to mow at the recommended height than from trying to gain some insulation against winter cold,” Upham said.
For common Kansas grass species, the recommended mowing heights for home lawns include:
- Tall fescue, 2 ½ to 3 ½ inches
- Kentucky bluegrass, 2 to 3 inches
- Buffalograss, 2 to 3 inches
- Bermudagrass, 1 to 2 inches
- Zoysiagrass, 1 to 2 inches
Upham said homeowners will need a reel mower to mow below 1 ½ inches.
“There may be some benefits gained by adjusting mowing heights within the recommended ranges at times,” he said. “For example, it is good practice to mow warm-season grasses at the higher end during late summer and early fall because this should help them store more carbohydrate reserves for the winter, and it may reduce the incidence of certain cool-weather diseases.
“But the rule to remember is to stay within the recommended height range for your species.”
Upham and his colleagues in K-State’s Department of Horticulture and Natural Resources produce a weekly Horticulture Newsletter with tips for maintaining home landscapes. The newsletter is available to view online or can be delivered by email each week.
Interested persons can also send their garden- and yard-related questions to Upham at [email protected], or contact your local K-State Research and Extension office.
FOR PRINT PUBLICATIONS: Links used in this story
K-State Horticulture Newsletter, https://hnr.k-state.edu/extension/info-center/newsletters/index.html
K-State Research and Extension local offices, www.ksre.k-state.edu/about/stateandareamaps.html
K‑State Research and Extension is a short name for the Kansas State University Agricultural Experiment Station and Cooperative Extension Service, a program designed to generate and distribute useful knowledge for the well‑being of Kansans. Supported by county, state, federal and private funds, the program has county extension offices, experiment fields, area extension offices and regional research centers statewide. Its headquarters is on the K‑State campus in Manhattan. For more information, visit www.ksre.ksu.edu. K-State Research and Extension is an equal opportunity provider and employer.
Story by:
Pat Melgares
785-532-1160
For more information:
Ward Upham
785-532-6173
