This is companion planting, weeds and roses. After a post hypothesizing if you sterilize the soil that maybe the beneficial microbes are terminated also, I tried this. The weeds do not kill the rose seedlings which germinate sooner. I tried a small bag of seedling mix this year and there is a lot of problems with killer fluffy mold.
Neil, Your “companion weeds” reminds me of this site, which points up the usefulness of microrrhizae (sp?) in undisturbed soil, esp., in the short term and its relationship to the health and productivity of the plant.
The moles disturb my rose bed soil quite a bit, but the symbiotic relationship I discovered is permitting the Petty Spurge to flourish prevents the danged rabbits from finding the new basals and other soft, succulent shoots on the roses. The worst downside of that is the rust which infects the spurge as the heat starts, staining my shoes rusty colored.