I took over my allotment in May last year and was lucky enough that it contains a 15 yr old grape vine in a Greenhouse. Last year I left it to do its own thing and just pruned it a bit and thinned out the grapes I got a loverly crop of grapes from it. In the Autumn then after reading various advice I trimmed it back, tidied it (it had been left to its own devices for about 2-3 years) and scraped the surface of the bark back.
I am now intending to re soil it as I don't know the last time the soil in the greenhouse was replaced.
My question, when I re soil should I also mix fertiliser in with the fresh soil directly around the roots, Or should I just mulch and fertilse the top of the soil to prevent risking damaging the roots? what is the best kind of fertiliser to use?