Start By Identifying the Weed, If Possible!
The best way to have your weed(s) identified is to take fresh samples (sealed in a plastic bag) to your local nursery and garden center.
The simple definition of a weed is a plant that's not wanted, or at least not wanted where it's growing. Weeds are plants that are well-suited to the local climate and growing conditions, which makes them prolific and resilient.
How you eliminate or control the weed depends on whether it's an annual, biennial, or perennial. Annual weeds complete their growth in a single season and have shallow roots. Annual weeds should be destroyed before they flower and make seeds. Perennial weeds are harder to remove since they may have large taproots, rhizomes, or runners that are hard to get rid of completely. The tiniest piece of root remaining after pulling a perennial weed can produce a new plant.
Weed Alert is a website that has a massive listing of weeds broken down into regions. They have a weed database that allows you to first identify a weed from a thumbnail photograph. Problem is, there are thousands of types and varieties of weeds! But if you have some extra time on your hands and want to learn more about and identify the weeds growing in your landscape visit WeedAlert.com
Chemical Weed Control In Landscape Beds
If you don't like living with weeds in your ornamental landscape beds, islands and natural areas, there are two options for control: 1) pull the weeds by hand or 2) spray the weeds.
When controlling weeds, there are several options based upon the type of weed. Basically, there are three types of weeds: 1) broad leaf weeds and 2) grassy weeds, and 3) brush or vining weeds.
Glyphosate-based Weed Killers
These are post-emergent products such as Killzall and Roundup. They are non-selective herbicides with a multiple-use formulation. They works quickly to eliminate broadleaf or grassy weeds, and many types of brush and vines, in non-turf areas, unless of course you want to use them to kill your existing lawn, or "weed patch" of a lawn, for renovation purposes. When used full strength, super-strength glyphosate products (41%) can be applied to stumps to prevent regrowth. They can also be useful to clean weeds from areas near fences, paths, patios, driveways, and buildings.
Glyphosate should be applied to actively growing weeds, preferably before the seed heads form. While glyphosate will control any plant you treat, it will not transfer through soil to neighboring plants.
Application should be made using a pump sprayer, hand sprayer, or hose-end sprayer. For best results, apply on warm, sunny, calm days when temperature is above 60 degrees F and rainfall is not expected within 24 hours. Though you can spray glyphosate around ornamental shrubs and trees, keep in mind that if the spray contacts the foliage of these plants that injury or death of the plant might occur. Therefore, pick a calm day when the wind isn't blowing to spray.
In order to avoid dumping too much chemical in the environment, I always recommend spot spraying weeds when using these chemicals. Spot spraying also uses less product, which saves you money.
Before spraying any chemical, always make sure to follow instructions on the label for mixing and application.
In addition to glyphosphates, there are other types post-emergent weed killers that work well to kill existing weeds in landscape beds.
Over-The-Top Weed Killers
These selective herbicides are designed to only kill certain types of weeds or grass plants while leaving others alone. For example, there are over-the-top weed killers that can be sprayed over the top of desirable ornamentals and groundcovers to kill Bermudagrass that has crept its way into a landscape bed. But hey, whose fault is that? Maybe the one who forgot to edge the lawn for 6 weeks? In any event, if you have Bermudagrass, or any other weedy grass growing in a groundcover planting, check with your local nursery and garden center to see what Over-The-Top weed killers they offer.
Weed preventers can be applied in ornamental landscape beds, islands and natural areas to kill weed seeds before they sprout. Check with your local nursery and garden center to see what weed preventer products they carry. Avoid using weed preventer / fertilizer combination products. Apply these products seperately for best results.