Helpline / Greenline

Master Gardeners help answer questions from the public as part of our "Greenline" project on subjects ranging from "what's killing my roses" to "how do I get rid of these potato beetles".  Calls can be placed to the local extension office and will be forwarded to the "on duty" gardener.  Go to our CONTACT tab for phone and email information.

Frequently asked questions:

Q: 

When and how do I prune Apple trees?

A

Apple tree pruning should be done during the dormant season, before active growth in the spring.  Older bearing trees should be pruned first while non-bearing, young trees should not be pruned until after Feb. 1.  Ideally, young apple trees should be “trained early”; pruning is used to redirect limbs, stimulate desired branching and remove growth in undesired locations.  However, in an older tree, the goal of pruning will be to open up the canopy and slowly bring it back to a cone shape in which the bottom of the tree is larger than the top.  Pruning should be done on a regular basis over a 2-3 year period and consist of many thinning cuts throughout the tree but with emphasis on the upper and outer portions of the tree.  Heading cuts should be made only in areas of low vigor where branching is desired.  Drooping, low hanging branches should be removed, as should crossing or damaged limbs and water sprout branches.  Also, if the tree requires lots of pruning, it is best not to apply nitrogen before or after pruning for 1-2 years. 

The Virginia Tech Extension publication, “Tree Fruit in the Home Garden”  contains more detailed information about apple tree pruning, as well as, descriptions of appropriate pruning cuts and angles. 

Q:

What is wrong with my pear tree,  flowers, shoots and fruit have shriveled and blackened.  The tips of the branches have a curled, hooked look and oozy streaks are running down the branches and bark of the tree How do I treat the diagnosed fire blight?

A:

 Fire blight is a bacterial infection.  The disease is common during warm, wet springs. 

 The VA Tech Pest Management Guide  (Home Fruit Diseases and Insects) gives instructions for chemical recommendations in the treatment of fire blight on pears.  Treatment of fire blight is very difficult and not always successful.  Pruning out new infections can help, with pruning shears dipped in a 10% bleach solution between cuts that are made well below the site of infection.  All pruned debris should be bagged and disposed of in the landfill.   The “Pest Management Guide” does have specific chemical recommendations and a spray schedule If that solution is acceptable.   Additionally there is an article from the University of California discussing the treatment of pear trees with fire blight.