Extension News

Ask the ISU Extension Gardening Experts

Note to media editors: Got gardening questions? Contact the Iowa State University Extension Hortline at (515) 294-3108 (Monday-Friday; 10 a.m.-12 noon and 1-4:30 p.m.) or send an e-mail to hortline@iastate.edu. For more gardening information visit us at Yard and Garden Online at www.yardandgarden.extension.iastate.edu.


There are tiny holes in the foliage of my eggplants.  What should I do? 

Flea beetles are the most common pest of eggplant in the home garden.  Adults are tiny, shiny, black beetles. They possess large hind legs that enable them to jump.  Flea beetles eat small, round holes in the eggplant foliage, resulting in “shothole” damage.  Minor flea beetle damage will have little effect on crop yields.  If significant damage begins to appear, treat plants with an insecticide.  As always, carefully read and follow label directions when using pesticides. 


Large portions of my lawn were recently flooded.  Will the grass die? 

In a flood, turfgrass areas can be damaged by the deposition of soil and other debris or by submersion under water. 


After short duration floods, all debris should be immediately removed from turfgrass areas. Soil deposits greater than ½ inch should also be removed. Using a garden hose, wash as much of the silt as possible from the lawn.  Finally, core aerate the affected area to promote recovery of the turf. 


Turfgrass areas that are under water for an extended period of time may be injured by a lack of oxygen and light, the accumulation of toxic gases in the soil, and other factors.  The degree of injury depends upon the turfgrass species, the duration of flooding, water depth, water temperature, and the condition of the turfgrass prior to the flood. Kentucky bluegrass is moderately tolerant of submersion under water. A healthy Kentucky bluegrass lawn should be able to survive several days submersed under water. After the flood waters recede and the soil begins to dry out, core aerate the affected area to facilitate the movement of oxygen into the soil. 


Do I need to deadhead my perennials? 

Deadheading is the removal of spent flowers. The removal of spent flowers is an important gardening chore for many perennials. 


The flowering period of perennials, such as coreopsis, garden phlox, Shasta daisy, and yarrow, can be prolonged by deadheading. Delphiniums often bloom a second time in late summer if the initial flower stalks are cut back after flowering. The removal of spent flowers on peonies and bearded irises promotes plant vigor by preventing the formation of seed pods. Deadheading also prevents the self-seeding of golden marguerite, yarrows and other potentially invasive perennials. 



Contacts :

Richard Jauron, Horticulture, (515) 294-1871, rjauron@iastate.edu

Jean McGuire, Extension Communications and Marketing, (515) 294-7033, jmcguire@iastate.edu