Question
Zone 8 Comox Valley - where should the bud union be positioned when planting roses? So many different instructions. Does it depend on the rose variety or the gardening zone?

Answer
The bud union needs to have some protection. If it is sitting above the soil then a strong wind could snap it off and you could also damage it when you were weeding around the bush. So planting it 3 or 4 inches under the soil is the best way. However if you want the rose to make it's own roots, then plant it 6 inches under the soil. You are right, it does depend on the climate in regards to the winter. If a person gets very cold nasty winters, then not only do you have to plant it 6 inches deep but also cover it up 12 to inches. The variety doesn't make a difference because the understock is usually a very tough rose. If the top modern rose is a poor grower and lacks vigor, it wouldn't matter even if you planted it deep, it would still cause trouble and be a poor rose. So in your area I would plant it about 3 inches below the soil level.