how many chill hours in my area

How are chill hours calculated?

Counting the Hours

One way to calculate chill hours is to count the number of hours with a temperature below 7°C (45°F). A slightly more accurate model excludes hours below freezing (as these do not contribute towards dormancy) and only counts those spent between 0°C (32°F) and 7°C (45°F).

How many chill hours does Zone 9 get?

Chilling Hours

Zone 8a 700+ Chill hours includes southern SC west to central TX	Premier, Climax Blueberry
Zone 9b 110-310 Chill hours includes extreme south TX	Anna, Dorsett Golden Apple, FlordaPrince, FlordaBest Peach, Tropic Beauty, Tropic Snow Peach, Sunhome Nectarine, Sharp, Misty, Gulf Coast Blueberry

What is considered a chill hour?

A chill hour is equal to one hour that a fruit plant or tree spends in cooler temperatures ranging from 45 to 32 degrees Fahrenheit. ... Some fruit trees, such as figs, only require 100 chill hours during the cool season. Others can require up to 1,000 chill hours. Tropical fruit plants and trees require no chill hours.

How many chill hours does Zone 10 get?

Chilling requirement is a concern for USDA zones 9B and 10, predominately in Southern and coastal regions where chilling hours average 100 to 600 per year. If you are within this area, take note of the chilling requirements listed for fruits and choose accordingly.

What are chill hours for blueberries?

Blueberry bushes need a minimum number of chill hours by variety each winter to enhance their fruiting. Chill hours are defined as hours less than 45°F but above 32°F. If a blueberry bush doesn't experience enough chill hours in the winter, the flower buds might not open at all in spring, or they might open unevenly.

How many chill hours do pistachios need?

Fruit & Nut Crop Chill Portions Requirements

Crop	Cultivar	Chill Portions
Pistachio	Peters²^,¹⁰	58-65
Pistachio	Sirora¹²	60
Prune	Improved French¹⁰	55-60
Walnut	Chandler¹⁰	45-50

Do chill hours need to be consecutive?

It is important to know that the Chilling Hours do not need to be consecutive. Typically, the plant just needs cumulative Chilling Hours. ... If we have enough nights doing that, then that may be enough for most plants. On the flip side, some plants have hair triggers to break out of dormancy.

What are the best fruit trees for Zone 9?

Zone 9 Fruit Tree Varieties

Owardi satsuma mandarin orange (Citrus reticulata 'Owari')
Calamondin (Citrus mitis)
Meyer lemon (Citrus x meyeri)
Marumi kumquat (Citrus japonica 'Marumi')
Trifoliate orange (Citrus trifoliata)
Giant pummelo (Citrus pummel)
Sweet Clementine (Citrus reticulata 'Clementine')

What is a low chill fruit tree?

Chill hours are the amount of time the fruit trees have spent below 45 degrees Fahrenheit. Low chill fruit trees, such as stone fruit, as well as nut trees, require a specific number of hours each winter to regulate growth.

Do pomegranates need chill hours?

Pomegranates like hot and dry summers but do require a minimum amount of chill hours to set sweet fruits. ... 'A.C. Sweet Pomegranate' can tolerate temperatures below 0 degrees Fahrenheit and can be grown in USDA zones 6 through 10.

What is the chilling temperature?

Chilling is the application of temperatures in the range of 0°C to 8°C, i.e. above the freezing point of the food, while freezing uses temperatures well below the freezing point, conventionally below 18°C. The difference between the two processes goes beyond the difference in temperature.

How many chill hours do strawberries need?

Most types of strawberry require 200-300 chill hours with temperatures between 45 and 32°F for optimal fruit production.

How many chill hours do peaches need?

Standard peach cultivars have winter chill requirements of 450 to 1,200 hours below 45 F between November 1 and the end of February. Those peach trees will not flower and set fruit in warmer climates.

How many chill hours do apples need?

Most apple varieties need 500-1,000 chill hours or temps below 45 F. (7 C.) but there are some low chill varieties available that need no more than 300 chill hours. Low chill varieties need less than 700 chill hours and can withstand hotter summers than other varieties.

How many chill hours does Houston get?

Within the Harris County area, Pasadena and the Galveston Bay area on the south side of the county receive approximately 350–450 chill hours; downtown Houston receives approximately 450 hours; Cypress and the Bear Creek area receive approximately 600 hours.

How cold can blueberries tolerate?

Cold Susceptibility

During the winter, dormant flower buds of highbush blueberries will survive temperatures as low as -20 to -30°F while the less hardy rabbiteye (V. ashei Reade) have survived -10°F but are often damaged below 0°F. As flowerbud swell progresses, cold tolerance decreases.

Why do plants need chill hours?

So, why do plants need chill hours? Plants need chill hours to act as a sort of natural clock to tell them when winter is over. That way, they can wait to start producing flowers until bees and other pollinators are active. They can also avoid loss of flowers and fruit due to late spring frosts and freezes.

Where is the best place to plant blueberry bushes?

Select a sunny, sheltered spot. While blueberries are tolerant of shade, better crops are obtained in the sun. At the same time, they should not be exposed to harsh, drying winds. Don't plant blueberries too close to trees, as the trees will not only block out sunlight, but will also suck up any moisture in the soil.

How many chill hours do almonds need?

The chilling requirement for almonds is 200-300 hours.

Do plum trees need chill hours?

Many fruit and nut trees that grow in temperate climates (climates that are moderate rather than extremely cold or hot) have chill hour requirements. Most temperate fruits, such as figs, pomegranates, olives, apples, pears, peaches, and plums require 200 to 2000 chill hours in the winter.

What is winter chill?

Winter chill, the extended period of cold temperatures critical for fruit and nut trees, is decreasing at certain sites in California's Central Valley. Serious economic loss could result if temperatures warm to a point when fruit and nut trees no longer experience sufficient winter chill. ...

Do citrus trees need chill hours?

Citrus and some other fruit trees don't have a chill hour requirement, but most do. Trees with low chill hour requirements are available.