Hello,
On my property I have plenty of hornbeam and dogwood transplants as well as some oak, dog rose and some other native plants.

I would like to plant a 50 meters long hedge and I would like it to be about 1.5-2 meters high in 2-4 years.

I would like it to be informal, natural looking hedge that I would trim once or mostly twice per year.

Would it work if I mix hornbeam with dogwood and other plants, or should I use hornbeam only since I have it most?
Should I plant in one or two rows, and how many plants per meter?

Thanks a lot,
Mountain