full sun mixed hedge
well i'm starting to gather all of the supplies and plants i need for starting my privacy hedge this fall and would love some advice from you guys. i have roughly 170' of fenceline that separates one side of my backyard from a sidewalk. my fence is a 6ft cedar fence (not a concrete block wall), and i have 4.5' of ground space between the outside of my fence and the barely-used sidewalk. this area faces W/SW and will get full sun from 11am-dusk during summers. i've decided on a fast-growing informal mixed hedge. the plants i've chosen are:
Red Bird of Paradise
Barbara Karst Bougainvillea (only 3 or 4 for more color interest)
i'm also considering using a groundcover as a "live mulch" and to keep down weeds while my hedges fill in. ideally this ground cover would extend beyond the fenceline to also border around my front yard so i dont have to maintain grass around my picket fence. the best groundcover choice would be about 1' high, very dense, fast growing, heat tolerant, and can survive on the same watering schedule as the hedge plants. i'm leaning towards creeping thyme or trailing rosemary but a groundcovering vine would work if it stayed off the fences and hedges, but that seems unlikely.
as for the hedge plants, i'm trying to calculate how many of what plants i need. i'm thinking a 4' spacing between plants would make a faster hedge, but perhaps this is too close for future hedge health? i'd like each plant to grow to at least the height of the fence (6'). but that brings me to my next question, how do i trim the plants off of the fence if i can't get between them? i dont really want to leave access gaps if i don't have to. how is this normally accomplished with large hedgerows?
any help or advice would be greatly appreciated.