Garden Column for the Salisbury Post

Darrell Blackwelder

March 18, 2004

     I receive a number of inquiries in March as the weather warms and the days get longer. Some days I can receive as many as 40 phone calls not including an increasing number of e-mails. Even though I enjoy speaking to people about their gardening problems, e-mail is the most efficient method of communicating. Gardeners can send a picture quite easily of insects or diseases which help me determine their problem. Below are questions I received over the past few days that many of you may identify.

     Question: When can I prune my rhododendron? Answer: Normally pruning is recommended after the bloom in early June.  

     Question: What is that purple weed in my yard and how do I control it?  Answer: The weed either henbit or deadnettle, both related to each other. Post emergence herbicides such as Trimec or Weed-B-Gon will control the weed, however during flowering the weed is difficult to kill.

     Question: I sprayed my weeds last week and they are not dying.  What is the problem?  Answer: Blooming broadleaf annuals are difficult and may be impossible to kill. These weeds are in the process of producing seed and not growing and therefore not adsorbing herbicides. Two herbicide applications ten days apart is an effect solution. Blooming annuals now will be dead in a few weeks as the temperature increases.

     Question: Can I over-seed my lawn now? Answer: Fescue can be over-seeded now, especially bare spots. Don’t wait too late in the spring.

     Question: Is it too late to apply pre-emergence herbicides to lawns?  Answer: No but apply them soon.  As the soil warms, crabgrass and goosegrass germinate making pre-emergence herbicides useless.

     Question: What can I do to keep worms out of my peaches? Last year I had a good crop but they were destroyed by worms.  Answer: Producing peaches trees are high maintenance and the fruit must be sprayed often, about every 14 days, with an insecticide to control insects. Home orchard sprays are available that contain both insecticides and fungicides necessary for insect and disease free fruit.

     Question: Is there anything I can do about blossom-end rot on tomatoes now?  I understand it is a calcium deficiency in the soil.  Answer: Blossom end rot is a calcium deficiency aggravated by many factors. Lack of calcium is one, but he major culprit is inconsistent irrigation practices; either not enough or too much. Some cultivars are more prone to the problem than others. Low pH levels are another factor. Have soil tested to determine if your pH is correct. Lime is beneficial in supplying calcium and raising pH. Irrigate on a consistent basis.

     Question: Can I divide my liriope now?  Answer: Yes, liriope is a lily and a tuff plant.  You can divide it most any time of the year and it survives. Fall is the best time.

     Question: Are you having any classes on lawn care?  Answer: I will be speaking on spring lawn care at the Historic Salisbury Flower and Garden Show on Saturday, March 27, at 10:00 a.m.

Darrell Blackwelder is an agricultural agent in charge of horticulture with the North Carolina Cooperative Extension Service in Rowan County. For archived garden columns or other information, visit the Rowan County Master Gardener web site at www.rowanmastergardener.com , e-mail Darrell_Blackwelder@ncsu.edu or phone at 704-633-0571.