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CHILLING REQUIREMENT OF TEMPERATE FRUIT TREES

The chilling hour requirement of fruit trees must be matched to the chilling hour zone where the tree is to be grown.  Your local county agent should be able to give you a list of cultivars that are adapted to your chilling hour zone.  Reputable nurseries should only sell fruit tree cultivars adapted to your region.  Below are the chilling hour requirements of selected cultivars of various fruit trees.

Crop Cultivar

Chilling Hour Requirement
Peach Red Haven 
Red Globe 
Sentinel 
June Gold 
Rio Grande 
EarliGrande

950
800
750
650
450
250
Cherry Montmorency

1000
Plum Ozark Primer
Methley

750
600
Apple Golden Delicious
Granny Smith

1000
600
Pear Maxine
Orient

850
650
Pecan Stuart
Desirable

500
400
Grape American cultivars
French cultivars

100
none
Citrus Most cultivars

none

 

What Happens if you Plant a Fruit Tree in the Wrong Chilling Hour Zone

The table below shows what happens if you plant peach cultivars with different chilling hour requirements in various chilling hour zones across Texas.

 Growth Response of Peach Cultivars With Different Chilling Requirements
if Planted in Various Chilling Zones Across Texas

Peach Variety

Chilling Hour Requirement

Brownsville
200 hour zone

College Station
600 hour zone

Wichita Falls
1000 hour zone

Earligrande

250

normal flowering

flowers early in spring, likely killed by late frost

flowers very early in spring, definitely killed by frost

June Gold

650

flowers late if at all; would still grow vegetatively

normal flowering

flowers early in spring, likely killed by late frost

Red Haven

950

flowers very late if at all; would still grow vegetatively

flowers late if at all; would still grow vegetatively

normal flowering