How do I control Weeds Effectively?
A weed is any plant that grows where it is undesirable. It's a simple as that. So a maize plant in a flower bed might be considered a weed (depending on the gardener's opinion) or a rosebush in a maize field might be considered to be a weed!
Generally, though, weeds are those upstarts that just take over, particularly on disturbed soil.
So how do I control them?
The first thing to remember, is that when you disturb soil, you're likely to get weeds, and that the sooner you control them, the easier it will be to keep it that way!
Since most weeds evolved to grow on disturbed soil, they like warm soil temperatures, moisture and exposure to grow. Covering the soil with mulch will quite often prevent the seeds from coming up.
All sorts of things can be used as mulch, but weed-free compost, sawdust or bark chips are favourites. Other options include pebbles or gravel or even grass clippings. When using grass clippings as mulch, check regularly to see if they are forming a mat that will repel water. A layer of permeable mulch about 5cm deep is sufficient to inhibit the growth of most weeds.
On farms, permeable weed netting or black plastic sheeting is often used to keep weeds down.
Prevent seeding at all costs
As soon as weeds make seed, you have months to years of future progeny. Control weeds before they seed, or the problem will never be resolved. If you don't have time to remove the weeds, cut them back with a brush cutter at or before flowering.
Mechanical control of weeds
This refers to pulling weeds out by hand or using forks, hoes or other implements to physically remove weeds. In small areas, or when there are enough hands available, this is the safest and most effective means of control.
Hand pulling is the best of these, as the soil is not disturbed so that new weed seeds are exposed to the light and warmth and begin to grow. It is important to remove roots, and if this is difficult, using a fork to loosen the soil is necessary.
Follow up with fresh mulch to limit the regrowth of weed seedlings.
When relatively large, clear areas need to be cleared of weeds, one can mow them, and then cover the area with anything that excludes light: black plastic sheeting, cardboard or old carpeting. Leave this in place for four to six weeks, and the chances are, all or most of the covered vegetation will have died.
Chemical control of weeds
This refers to spraying the weeds with herbicide or applying granular herbicides.
At all times, ensure that you carefully read the product information leaflet to determine safety precautions and correct dosage and application instructions.
Many herbicides have been connected with cancer, so use all the necessary safety precautions.
Never spray under windy conditions, as the drifting spray might affect desirable plants or even people and animals.
Herbicides may be post or pre-emergent, selective or non-selective.
Pre-emergent herbicides are applied to soil after cultivation to prevent seed germination. Be careful not to work them into soil as this may affect other plants.
Post-emergent herbicides are applied after the weed has begun to grow. Most of these have an action based on leaf surface absorption of the chemical, so the weeds should have fresh, new growth.
If they are very tall, first brush cut them, allow at least two weeks for foliage recovery and then spray.
Non-selective herbicides kill all plant material in a period of days to weeks depending on the mode of action whilst selective herbicides only kill certain plants. For example, broad leafed weeds in turf-grass are often controlled with selective herbicides.
Get them while they're young!
No matter what type of weed you're controlling or what strategy you use, the younger the plant, the easier it will be to eradicate and the less disturbance you will cause to the soil and surrounding plants.
Success with weed control requires alertness and persistence as well as a little help from nature.
Go Back to Home and Garden for more
Edited by: Rajesh Bihani ( Find me on Google+ )