From time to time our Planting to Grow newsletter subscribers write to me to ask a specific question or to suggest a possible topic idea for an upcoming newsletter. Below you will find a question that was recently asked and how I responded. Hopefully, you will find this information helpful in your own yards.
Question: I want to cover the ground in my island bed with something that won't allow weeds to grow up, into, and through. I have considered placing gravel on top of landscape fabric. A neighbor did something similar with hardwood mulch but the grass still continued to grow through it. What could you suggest for a lasting solution to weeds popping up in an inland bed?
Answer: There isn't a lasting material that will not eventually allow weeds to grow through, except a hard paved surface like concrete, asphalt, or pavers. Landscape fabric material works fine until falling leaves decompose and make a humus layer between the rocks. Weed seeds get blown into the gravel and germinate in the humus.
My personal preference is to first put down a pre-emergent weed control, then a good thick layer of pine straw. The pine straw initially will be about 12 to 16" tall, but in a week will settle to 3-4" inches. The pine straw will do a good job at shading out most of the weeds. For those few weeds that do persist I spray with a bottle of Roundup during the growing season.