Q: I have a lot of trouble keeping grass from growing into my flower beds. Is there something I can kill the grass with that won’t hurt my other plants?
Yes, there are herbicides that kill only grasses, without harming other kinds of plants or causing serious environmental problems. Any independent garden center will carry two or three different brands. But before purchasing be sure the label clearly says it is for the control of grasses alone. Use according to directions; these herbicides work best when the grasses are small or young, and actively growing—not cold and dormant, or hot and dry, or starting to flower.
However, though I am not personally or professionally opposed to the occasional use of carefully-selected pesticides, and occasionally use one for specific weeds like poison ivy in my own garden, herbicides are not my first choice for weed control. In addition to being expensive and not entirely easy to use safely, they also have possible side effects both on nearby plants and your own health.
Two Times is Better than One
I’m as lazy a gardener as can be, so you know I don’t enjoy pulling or chopping weeds. But sometimes it is the best approach. I find it a lot easier a day or so after a good rain or watering, which helps the grass and other weeds come up easier.
I have found it to be a lot easier to pull regularly, when weeds are small and before they get well-established. I keep after it rather than waiting until stuff is big and deeply rooted. As the saying goes, “It is easier to weed twice than once.“ By the way, I have learned to appreciate my foam knee pad, available at many garden centers, for protecting my jeans and my knees.
The “Fort and Moat” Approach
To most folks, the easiest way to keep the lawn from encroaching into flower and shrub beds is to use either a physical barrier—edging—or a small ditch the weeds have a hard time crossing.
Hard borders can be made of long bands of vinyl or metal edging pushed part way into the ground, or with bricks, pavers, terra cotta tiles, or even wine bottles sunk neck-down. Make sure they are sunk enough to keep grass from growing underneath, and easy to mow next to or not likely to be chewed up with a string trimmer.
However, the so-called “English border” both looks and works well. It is simply a shallow ditch dug between the flower bed and lawn, typically with the side facing the lawn cut straight down for a crisper, cleaner look, and the soil from the ditch thrown up into the flower bed. It doesn’t take long to dig the first time, especially when the soil is moist enough to dig easily, and if you keep a metal file handy to keep the blade of your spade sharp, it makes for easier digging.
Once established, a border ditch is easy to maintain or clean out when needed. It not only gives a nice edge to the lawn, but makes spotting weeds easier as they first start to cross the ditch.
Gardening expert and certified wit Felder
Rushing answers your questions and lays down some green-wisdom. You can
get more of your Felder fix at www.slowgardening.net.