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


When would be a good time to dig and divide lilies? 

Early fall is an excellent time to dig and divide Asiatic, Oriental and other garden lilies.  Carefully dig up the clump and separate the bulbs. Replant the bulbs immediately. (If planting must be delayed, place the bulbs in a plastic bag containing lightly moistened peat moss and place the bag in the refrigerator.)  Plant the large bulbs 4 to 6 inches deep. Small bulbs should be planted 1 to 2 inches deep. Lilies perform best in well-drained soils in full sun.  The large bulbs may bloom the following summer. However, the small bulbs may not bloom for one or two years. 


Can oak leaves be used as a garden mulch? 

Yes.  While oak leaves are slightly acidic, an oak leaf mulch should have only a minimal effect on the soil pH.  Shredded leaves are an excellent mulch for vegetable gardens, raspberry plantings, perennial flower beds and around trees and shrubs. Oak leaves can be shredded with a lawn mower or a leaf shredder. 


How can I germinate walnuts? 

Collect walnuts after they fall to the ground.  Remove the husks and place the nuts in water. The nuts that float are not viable and can be discarded. Good, viable nuts will sink to the bottom. 


Before the walnuts will germinate, the nuts need to be exposed to cold temperatures and moist conditions. The cold-moist requirement can be met by planting the nuts in the ground in fall.  Plant walnuts 1 to 2 inches deep. 


The cold-moist requirement can also be accomplished through a process called stratification.  Walnuts can be stratified by placing the nuts in a moist mixture of sand and peat moss and storing them in a cool location. Suitable containers include coffee cans, plastic buckets and food storage bags. The refrigerator is a good storage location.  (Stratification temperatures should be just above freezing.)  The walnuts must remain in the refrigerator for 90 to 120 days. After the nuts have been properly stratified, they can be removed from the refrigerator and planted. 



Contacts :

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

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