With the cold temperatures occurring in the area its good to know the critical temperatures at different bud stages listed below. From http://www.tfrec.wsu.edu/pages/cpg/Critical_Temperatures
Critical Temperatures / Bud Death Table | |||||||
(from WSU Extension) | |||||||
Bud Stage | |||||||
1 | 2 | 3 | 4 | 5 | 6 | 7 | |
degrees Fahrenheit | |||||||
Apple | |||||||
silver tip | green tip | 1/2 inch green | tight cluster | first pink | full pink | first bloom | |
10% kill | 15 | 18 | 23 | 27 | 28 | 28 | 28 |
90% kill | 2 | 10 | 15 | 21 | 24 | 25 | 25 |
Pear | |||||||
buds opening | buds exposed | tight cluster | first white | full white | first bloom | full bloom | |
10% kill | 15 | 20 | 24 | 25 | 26 | 27 | 28 |
90% kill | 0 | 6 | 15 | 19 | 22 | 23 | 24 |
Peach | |||||||
first swelling | calyx green | calyx red | first pink | first bloom | full bloom | postbloom | |
10% kill | 18 | 21 | 23 | 25 | 26 | 27 | 28 |
90% kill | 1 | 5 | 9 | 15 | 21 | 24 | 25 |
Apricot | |||||||
first swelling | tip separates | calyx red | first white | first bloom | full bloom | in the shuck | |
10% kill | 15 | 20 | 22 | 24 | 25 | 27 | 27 |
90% kill | − | 0 | 9 | 14 | 19 | 22 | 24 |
Plum (Prune) | |||||||
first swelling | side white | tip green | tight cluster | first white | first bloom | full bloom | |
10% kill | 17 | 20 | 24 | 25 | 26 | 27 | 28 |
90% kill | 3 | 7 | 16 | 20 | 22 | 23 | 23 |
Cherry | |||||||
first swelling | side green | tip green | tight cluster | open cluster | first white | first bloom | |
10% kill | 17 | 22 | 25 | 26 | 27 | 27 | 28 |
90% kill | 5 | 9 | 14 | 17 | 21 | 24 | 25 |
Additional information
New cherry bud hardiness information from OSU
http://extension.oregonstate.edu/wasco/sites/default/files/cold_frost_and_dead_buds.pdf
Blog from OSU David Gibeaut http://blogs.oregonstate.edu/gdavs/