Extension News

Ask the ISU Experts

Note to media editors:

Got gardening questions? Contact the 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.


What is the proper way to harvest and store winter squash? 
Harvest winter squash when the fruit are fully mature. Mature winter squash have very hard skins that can’t be punctured with your thumbnail.  Additionally, mature winter squash have dull-looking surfaces. 

When harvesting winter squash, handle them carefully to avoid cuts and bruises. These injuries are not only unsightly, they provide entrances for various rot-producing organisms. Cut the fruit off the vine with a pruning shears. Leave a 1-inch stem on each fruit. 

After harvesting, cure winter squash (except for the acorn types) at a temperature of 80 to 85 degrees F and a relative humidity of 80 to 85 percent. Curing helps to harden their skins and heal any cuts and scratches. Do not cure acorn squash. The high temperature and relative humidity during the curing process actually reduce the quality and storage life of acorn squash. 

After curing, store winter squash in a cool, dry, well-ventilated location.  Storage temperatures should be 50 to 55 degrees F.  Do not store squash near apples, pears or other ripening fruit.  Ripening fruit release ethylene gas, which shortens the storage life of squash. 

When properly cured and stored, the storage lives of acorn, butternut and hubbard squash are approximately 5 to 8 weeks, 2 to 3 months and 5 to 6 months, respectively.

There are brown streaks in my apples.  What is the cause and how can it be prevented? 
The brown streaks in the apples are probably due to the apple maggot. The apple maggot is the most serious insect pest of apples in Iowa. Apple maggot damage appears as knobby, misshapen fruit with small pits or blemishes on the fruit surface. In addition, brownish streaks run through the flesh of the apple.  The apple maggot is occasionally referred to as the “railroad worm” because of the slender brown streaks or tracks in the apple’s flesh. 

The apple maggot is a type of fruit fly. Female apple maggot flies insert eggs beneath the skin of fruit from about mid-June until shortly before harvest. The punctures produce small holes that later appear as blemishes on the fruit. Upon egg hatch, the larvae tunnel through the flesh of the apple producing the distinctive brown streaks. 

Control of apple maggot is difficult. Picking up and destroying apple maggot infested apples that have fallen to the ground is somewhat helpful. Placing apple maggot traps (red spheres or yellow cards coated with a sticky substance) in apple trees usually provide satisfactory levels of control.

Insecticides are the most commonly used method of controlling apple maggots in commercial and home orchards. Insecticides should be applied from mid-June through September. Suitable insecticides for home gardeners include Sevin and any of the “multi-purpose fruit tree” sprays.  Despite regular spraying, apples in many home gardens suffer substantial apple maggot damage due to poor spraying techniques, rainy weather and other factors. 

What are grape hyacinths? 
Grape hyacinths (Muscari spp.) are spring-flowering bulbs. They produce urn-shaped flowers (which somewhat resemble grapes) on 6- to 9-inch-long, upright spikes.

Flowers are typically shades of blue or violet, but there also are white and yellow flowering varieties. Grape hyacinths perform best in well-drained soils in partial shade to full sun. They are best used for edging beds, in rock gardens, and naturalized drifts.  Plant grape hyacinths bulbs 3 to 4 inches deep and 3 to 4 inches apart.

Contacts :

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

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