Extension News

Ask the ISU Extension 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.


Is it a good practice to apply salt to an asparagus planting? 
In the past, some gardeners used salt to control weeds in their asparagus plantings.  However, salt is not effective in controlling many weeds, especially grasses.  Plus, continued use of salt over several years may result in high salt levels in the soil.  High levels of salt may actually damage the asparagus.  In the home garden, shallow cultivation and hand pulling are the best ways to control weeds in an asparagus planting. 

What is the difference between bulbs, corms, and tubers? 
Bulbs, corms and tubers are all underground food storage organs. 

A bulb is composed of fleshy leaves attached to a compact stem (referred to as the basal plate). The basal plate is located at the bottom of the bulb. The outer layer of leaves of some bulbs, such as tulip and daffodil, dry and form a protective, paper-like covering (tunic) for the bulb.  Other bulbs, such as lilies, have no protective bulb covering. 

A corm is the enlarged base of a herbaceous plant stem.  Being a stem, a corm contains nodes and internodes. Corms also may have dry, tunic-like protective coverings. The corm’s nodes and internodes are easy to see when the dry, paper-like covering is removed.  Examples of corms include gladiolus and crocus. 

A tuber is a fleshy, enlarged portion of an underground stem.  A common example is the Irish potato.  Tubers do have buds or “eyes”, but don’t have protective, tunic-like coverings. 

When is the best time to transplant an azalea? 
Early spring (before the shrub begins to leaf out) would be the best time to transplant an azalea.  In Iowa, this would normally be sometime between late March and mid-April. An azalea transplanted in fall (after leaf drop) would be susceptible to winter injury. 


Contacts :

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

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