Dorsett Golden Chill Requirements

Dormancy

• Dormancy is the cold period during which apple trees lose their leaves and develop their flower and leaf buds for the upcoming warm season. Temperatures that are between 32 and 45 degrees Fahrenheit allow the buds to form normally. Each apple cultivar has a chilling requirement, which is the number of hours that a tree must remain in this temperature range. After its chilling requirement is met, the tree’s flower buds open in response to warm weather and the fruit can develop. But if a tree experiences insufficient chilling time, it may set little or no fruit, and the fruit that develops may be poor quality.

Chill Hours

• Chill hours represent the range between 32 and 45 degrees F but they do not have to be accumulated continuously on successive days. Instead, they represent a total hourly accumulation during a plant’s dormancy period, which are the coldest months of the year in any region -- roughly the timeframe between the first and last frost dates. Although manually calculating the chill hours in your region would be tedious work for you, your local extension office maintains and updates this data yearly.

Low-Chill Apples

• Most apple trees require 500 to 1,000 chilling hours before they can set fruit buds. Low-chill apples are the varieties that need less than 500 chill hours to set fruit. These trees flourish in areas that have mild winters, but they are decidedly the minority among apple varieties. The “Dorsett Golden” apple tree is native to the Bahamas. Because it is adapted to a warm climate, it can produce apples with only 100 chill hours.

"Dorsett Golden"

• “Dorsett Golden” grows in U.S. Department of Agriculture plant hardiness zones 5 through 10, where it has one of the lowest chilling requirements of all apple cultivars. It is so warm-weather adaptable that it prospers even in areas that receive no winter chill, including desert regions. It is a crisp, sweet apple that is similar in flavor to “Golden Delicious,” and it is a long-keeper, storing well for two months. Unlike many apple trees, “Dorsett Golden” is self-fruitful, which means it does not require another cultivar to pollinate it -- you can plant only one tree to harvest fruit.