Here is a short list of pears adapted to colder climates (hardiness zones 2, 3 and 4).

European Pears (Pyrus communis)
Will require another European pear for cross pollination.
- ‘Barlett Rouge’ zone 4b
- ‘Flemish Beauty’ zone 4 (partially self-fertile)
- ‘Julienne’ zone 3 (partially self-fertile)
- ‘Loma’ zone 3 (partially self-fertile)
- ‘Lorraine’ zone 3 (partially self-fertile)
- ‘Luscious’ zone 3b
- ‘Northbrite’ zone 3 (partially self-fertile)
- ‘Patten’ zone 4
- ‘Savignac’ zone 3
- ‘Southworth’ zone 3 (partially self-fertile)
- ‘Ste-Sophie’ zone 3
- ‘Summercrisp’ zone 3b
Manchurian Pear (P. ussuriensis and its hybrids)
Will require another Manchurian pear or a hybrid Manchurian pear (P. ussuriensis x P. communis) for cross pollination.
- Early Gold ‘Jefgold’ zone 2
- ‘Golden Spice’ zone 3
- ‘Ure’ zone 2

Asian Pear (P. pyrifolia)
Most are at least partially self-fertile, but produce best when another Asian pear is available for cross pollination.
- ‘Chojuro’ zone 5 (4b) (partially self-fertile)
- ‘Hayatama’ zone 4b
- ‘Kenko’ zone 4b (partially self-fertile)
- ‘Shinseiki’ zone 4 (possibly zone 3b)
- ‘Shinko’ zone 5 (4b) (partially self-fertile)
- ‘Taylor Apple Pear’ zone 4 (possibly zone 3b)
I planted Bosc, a Flemish Beauty and a Chojuro Pear tree. Do I still need another pollinator? Will Golden Spice work?
Bosc and Flemish Beauty are both European pears and will pollinate. Chojuro is an Asian pear and usually won’t cross with them. It needs an Asian pear. Golden Spice is a Ussurian hybrid and will cross best with Ussurians.
why can’t an european pear pollinate russian pears yet their are ussuriensis x communis hybrid ?
Special hybridizing techniques are used to force the (female) flower to accept the (male) pollen.
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