no idea about your hedge, but thought i'd comment on the climber - i've lived in two houses now where jasmine has been planted in shady areas and has thrived. one was under a carport, the other (this house) was under a pergola. the one we pulled out here had been here for 20 or more years, and it had the thickest trunk i'd ever seen on a climber! was divine - the only reason we took it out was because it had been left to get out of control, was intertwined with ivy, and had gotten wrapped around the fence (which was falling down from the age of it). loved that plant! very hardy, lovely scent, and the flowers are very cute.