Harnett County Center
TIPS FOR WEED CONTROL IN THE LANDSCAPE, 7/26/98
If only roses grew like crabgrass. It seems that weeds are about the only things that are thriving right now. Controlling weeds is certainly a worthwhile endeavor. Not only do they compete with your flowers and vegetables for nutrients, light, and water, they can also provide habitat for pests to hang out.
To develop a weed control strategy, consider how a weed thinks. Weeds are opportunists. In fact, many weeds are downright lazy (okay, so kudzu is one of the exceptions).
In other words, weeds tend to colonize a spot where there is no competition. A thick healthy stand of grass is much less inviting to weeds than a patchy lawn with bare spots.
So the priority is to give your plants all they need to grow full and healthy. Weeds need light, water, and nutrients to grow. If your flowers and shrubs are taking good advantage of these resources, little will be leftover for the weeds.
You shouldn't wait until you see weeds to take action. There are many preventive strategies which will make your job easier.
For example, in a vegetable garden or flower bed, do a good job of eliminating existing weeds before planting. For tough perennial weeds like bermudagrass (a.k.a. wiregrass) or nutsedge, a systemic herbicide should be used. Systemic herbicides are absorbed by the plant and kill it at the root.
Once you have taken care of these, till the soil deeply in preparation for planting. Tillage will expose new weed seeds to the surface, encouraging them to germinate. Wait a week or so for the flush of new weeds, then cultivate lightly to remove them. Don't disturb the soil too deeply, or you will start the cycle over again. After planting, a two or three inch mulch layer will help prevent new weeds.
But you may have an existing planting that has a severe weed infestation. If the plants look like they are unhealthy, a soil sample might be a good idea. This will reveal any soil problems that are preventing your plants from growing vigorously, and competing more effectively against the weeds.
Herbicides are definitely an important weed control weapon. When using herbicides, it is critical to choose the correct one and use it correctly. Herbicides are quite effective, but if they are applied at the wrong time or by the wrong method, the results will be disappointing.
Pre-emergent herbicides are applied before the weeds germinate and have no effect on existing weeds. Post-emergent herbicides are used on existing weeds. In general, most weeds are easiest to control when they are small. Weeds should definitely be controlled before they set seed.
There are two categories of post emergent herbicides; those which can be applied "over the top" of your flowers, lawn, etc., and those which must be applied as a "directed spray" to the weed only. When using the "directed spray" technique, be sure to avoid damage to your desirable plants. Apply during calm conditions to prevent drift.
As I often mention, reading the instructions is critical. It will tell you which weeds are controlled, and in which crops it can be used.
Many times when we see a weed problem, our first question is "what can I spray to kill it?" I think a better approach is to first find out why the weed problem exists in the first place and if there are any steps you can take to correct it.
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