Colorado might be a tough climate if they bloom early. Might be lots of years the blooms get frosted. If you decide to go for it I suggest you choose an area that the soil warms up late. If you have a place that slopes north would be best. Also an area that snow tends to linger on the ground would be a good choice. Having a thick mulch also keeps the ground from quickly warming in the spring. These things might delay blooming a week or two.

Hi gjcore,

I went ahead and ordered 2 trees from Trees of Antiquity. I figure that I have about an 80% chance of a decent crop in a given year. Apparently, in the horizontal espalier form, pear trees overfruit pretty radically. In a normal year, 75-90% of the fruits need to be thinned. The frost may do some pre-thinning for me in some years.

My chances of getting crop are zero if I don't try.

The spot is set and the reason to try - a large blank area on the wall of the west side of my house. Afternoon sun, very good drainage.

I gave a shot to 20th century asian pear. zone 5,