grass killing in ornamental beds
Hi! I have many ornamental beds, many with native flowers, and I have grass creeping in. is there an effective grass killing spray that wont hurt the ornamental plants? I tried one from the Home Depot and it didn't seem to work very well. Any suggestions for a product to try? Thank you so much!
When you say the grass is "creeping in" to your beds, we assume you mean from the outside edges, coming from the lawn? For that we'd suggest using a sharp shovel to give the beds a fresh 3-4" deep edge and weed out the grass/weeds that are encroaching. Some turf grasses 'tiller' or spread this way, but so do more aggressive grassy weeds like crabgrass, which is much easier to control and pull when they are smaller.
If you mean grasses are seeding into the bed, perhaps like Japanese Stiltgrass, they are easy to pull and we suggest that. Herbicides that are labeled for grass control are not always effective as you've found.
Figuring out what weed you have is important for figuring out the best way to stop them. For instance, for stiltgrass you'd want to avoid letting them go to seed. Since they are an annual, a pre-emergent in the spring applied to problem areas is an option. If you can be careful with application, a non-selective herbicide containing the active ingredient glyphosate is also an option.
Look at our weed gallery photos and information here: http://extension.umd.edu/hgic/problems/problem-weeds