Here is another trick Bernie Nikolai from Edmonton Alberta Canada uses
“Ultra Hardy Dwarf Pear Rootstock
If you want a dwarf ultra hardy pear rootstock, graft pears onto cotoneaster, the common hedge plant hardy to zone 2. The graft union is long lasting for many decades (there are pear trees on cotoneaster rootstock in Russia over 50 years old). However you absolutely must have a few branches of cotoneaster coming under the graft of the pear to feed the cotoneaster rootstock, or the graft will die. The pear graft takes all the nutrition from the cotoneaster rootstock, but hardly gives anything back, so cotoneaster branches are required to feed the roots.
The pear tree will only grow to about 6 or 8 ft tall, and will start to give pears in the 3rd year after grafting (sometimes even the 2nd year). The pear is hardier on cotoneaster than on normal pear rootstock, as the cotoneaster causes the pear to go dormant at least 2 weeks earlier in the fall. Surprisingly the pears are slightly larger on cotoneaster than on pear rootstock, plus they taste a bit better based on tests in Russia. You can get up to 25 kgs of pears on one of these dwarf pear trees once they mature.
Below is a photo of some of my experimental pear trees on cotoneaster here in zone 3 flowering in the 3rd year after grafting. The more cotoneaster branches growing under the pear graft, the better the pear grows. The only problem with this rootstock is cosmetic. Some folks think the trees look “untidy” due to the appearance of the feeder cotoneaster branches at the base.
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