The nemesis of every gardener is of course, "the weed." If you're going to garden, you're going to have weeds. To put it another way, it was easier for U.S. Special Forces to get rid of Osama Bin Laden than it will be for you to free your yard of weeds.
A spring breeze can carry millions of seeds across the county and into even the most manicured of gardens. So what can you do to reduce your weed problem?
First, know your enemy. Weeds are plants, undesirable ones but still plants. This means weeds need light, water and nutrients to survive. Eliminate one or more of these and you can cut down on weeds in your yard.
Another important fact is that most weeds spread by root or by seed. Of the two, seed-borne weeds are the more difficult to deal with.
Among the most popular techniques for dealing with weeds are spraying, applying a pre-emergent, rototilling, mulching and covering the entire yard with groundcover cloth.
In most cases I would discourage using groundcover cloth; it will only stop weeds that are beneath it. Anywhere the cloth is exposed to sunlight, weeds will find a way through. If you cover the cloth with bark, mulch or rock you have reduced chances of sunlight getting through, but you have also created a new layer of material in which weed seeds can settle and grow.
I suggest using a groundcover cloth only as a way to keep bark and rock from working its way into the soil, not as weed prevention.
As an alternative to a cloth, use layers of newspaper on beds and top with mulch or compost. The newspaper will act like a groundcover cloth for a season or two then biodegrade, while the top mulch will hide the paper, block sunlight and add nutrients to the garden.
The best technique for dealing with weeds is to dig out the ones you can see, then rototill or turn garden beds occasionally to disturb the roots of existing weeds and keep seeds from germinating. This, however, is a bit time consuming and many people will opt to cover their gardens with mulch to slow weed growth - a great technique for beds that have minimal problems but not to control those that have been overrun with weeds.
Spraying and pre-emergents are another way of dealing with weeds. Round-up is the most recognized spray and reacts within a couple of days when applied on weed foliage. But it does not affect seeds or weeds germinating below the surface. The use of foliar sprays, if not combined with other techniques like mulching or rototilling, will require the repeated spraying of an area to maintain control. I suggest using such sprays primarily as a way to kill weeds that have overtaken a garden, then return to the other methods for continued control.
Pre-emergents are products applied to the soil to prevent weed seeds from germinating. These can be effective for several months if properly used but they will have no affect on weeds that have already germinated.
And so the battle goes. But whatever tactic you use to root out undesirables, I suggest you take a lesson from the Navy Seals and pursue your weed problem with dedication and perseverance.