Hi. I’m looking for a narrow screening / privacy hedge (approx 60cm wife and 3m tall ) along a 7m southern fence ( to be planted in a raised garden bed) in Perth. I would like to underplant with some annuals and pleach the hedge. I have looked at the port wine magnolia as well as the viburnum odoratissmim - I like the freshness of their lime green foliage. Will either have root or other issues right up the fence? How long before they reach 3m. Any advice is welcome.