Can I weed-whack overgrown rosa rugosa and cover in plastic to remove it from our landscape?
Question:
I have a large area of rosa rugosa in the yard of the house I moved to last year. We would really like to remove/kill it so that it does not continue to take over the rest of the yard and plantings. The area is around 100 feet by 20 ft currently, so digging plants out one by one would be extremely time consuming and I am not keen to use herbicides as recommended online. I am wondering whether I might have success by weed-wacking the plants down and then covering in black plastic for a year. That would be the simplest and most economical method for me, and I am interested to know whether you think it could work. I haven’t seen anything online about doing that one way or the other for rugosa.
Answer:
The approach you are wondering about will work most of the time, and is in fact a non-toxic method we often recommend for getting rid of weeds–there aren’t that many plants that will outlast a concerted, dogged effort to deny them the critical photosynthetic machinery of their foliage. But I do want to temper your expectations regarding time. It might take several seasons of being smothered before the plants are truly dead. In addition, you might consider covering the black plastic (or heavy landscape fabric, cardboard, thick layers of old newspaper, etc.) with a layer of soil or mulch to improve the effectiveness of the barrier. Anything you can do to make the layer on top of the roses pressed down and lightless. You will still get some sprouts poking through, especially at the edges, so keep them immediately cut back. Once you are sure it’s under control, you can remove the smother (if your barrier was non-biodegradable) or plant into the soil (if your barrier was biodegradable). In the former case, you might consider solarization of the exposed soil–basically covering the soil with clear plastic for a few weeks early in the season in order to create a mini-greenhouse effect and kill weed (and in this case, rose) seeds in the soil.