Posted: 14/02/2016 at 13:18
I find that experts older than me plant with the union above ground.
Experts younger than me bury the graft union.
I plant with the graft well below ground. Apart from any other reason, I find that in windy East Anglia, if the shrub is planted deeply it helps prevent wind-rock.
I've seen old HT roses with the graft above ground suffer really badly from wind-rock, which encourages the growth of suckers from the rootstock.