I'm wanting to plant a hedge along this fenceline to block out the road. I've engaged a landscaper who has recommended and quoted on planting 1.5m tall photinia trees along the fenceline with 800mm spacing.
I've seen lots of other houses around my area with photinia hedges so it's definitely suited to the area, but my concern is that I have tall gum trees that partially shade the fenceline. I can't cut down or even really prune the trees so they will always be there.
I understand that photinia prefers full sun and that I'm not going to get optimal growth by planting them here, but will they still grow and form a decent hedge? The landscaper is charging a lot of money (it's a long fenceline) so I'd hate to spend that much and have them struggle or even die altogether.

