Hi MTG,
I replaced my fence with a hedge of Hornbeam saplings about 3 years ago (during the winter). I chose hornbeam as they are suited to clay-like soils and they shouldn’t loose their leaves in winter (they turn brown like Beech trees)
I spent a little extra and bought 6ft saplings which, once planted I trimmed by 50% down to 3 foot. This is a little more trimming than most recommend, but I wanted to make sure they bushed out.
Plus, I ordered the plants and then it snowed/froze for about 3 weeks so the plants were in the shipment wrapping for more than three-times the recommended duration. By trimming them heavily and making sure they were planted on a good quantity of compost I didn’t loose a single plant.
I didn’t use pesticide or vast quantities of mulch, but hand-weeded to ensure big weeds didn’t compete with the new plants (didn’t worry about small weeds).
This past summer was the first one where it actually looked like a proper boundary (i.e. you couldn’t see through it and it grew to about 5 foot high).
despite the long time to maturity I still think it was an excellent move as by now I would have replced the fence panels at least twice due to them being blown over!
Hope this helps,
Ben