
Winter wheat (usually ''
Triticum aestivum
Common wheat (''Triticum aestivum''), also known as bread wheat, is a cultivated wheat species. About 95% of wheat produced worldwide is common wheat; it is the most widely grown of all crops and the cereal with the highest monetary yield.
...
'') are strains of
wheat that are planted in the
autumn
Autumn, also known as fall in American English and Canadian English, is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, in September (Northern Hemisphere) or March ( South ...
to germinate and develop into young plants that remain in the vegetative phase during the winter and resume growth in early spring. Classification into spring wheat versus winter wheat is common and traditionally refers to the season during which the crop is grown. For winter wheat, the physiological stage of heading (when the ear first emerges) is delayed until the plant experiences
vernalization, a period of 30 to 60 days of cold winter temperatures (0° to 5 °C; 32–41 °F).
Winter wheat is usually planted from September to November (in the
Northern Hemisphere
The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's North ...
) and harvested in the summer or early autumn of the next year. In some places (e.g.
Chile
Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east ...
) a winter-wheat crop fully 'completes' in a year's time before harvest. Winter wheat usually yields more than spring wheat.
So-called "facultative" wheat varieties need shorter periods of
vernalization time (15–30 days) and temperatures of 3° to 15 °C (37–59 °F). In many areas facultative varieties can be grown either as winter or as a spring, depending on time of sowing.
In countries that experience mild winters, such as in South Asia (India, Pakistan, Nepal, Bangladesh), North Africa, the Middle East and the lower latitudes (e.g. Sonora in Mexico), spring wheat (not requiring a period of
vernalization) is also sown in the autumn (November–December) and harvested in late spring (April–May) the next year. This spring wheat planted in the autumn and grown over the winter is sometimes also incorrectly called "winter wheat".
Hard winter wheats have a higher
gluten
Gluten is a structural protein naturally found in certain cereal grains. Although "gluten" often only refers to wheat proteins, in medical literature it refers to the combination of prolamin and glutelin proteins naturally occurring in all grain ...
protein content than other wheats. They are used to make flour for
yeast bread
Bread is a staple food prepared from a dough of flour (usually wheat) and water, usually by baking. Throughout recorded history and around the world, it has been an important part of many cultures' diet. It is one of the oldest human-made ...
s, or are blended with soft spring wheats to make the all-purpose
flour
Flour is a powder made by grinding raw grains, roots, beans, nuts, or seeds. Flours are used to make many different foods. Cereal flour, particularly wheat flour, is the main ingredient of bread, which is a staple food for many cultures ...
used in a wide variety of baked products. Pure soft wheat is used for specialty or cake flour.
Durum, the hardest wheat, is primarily used for making
pasta
Pasta (, ; ) is a type of food typically made from an unleavened dough of wheat flour mixed with water or eggs, and formed into sheets or other shapes, then cooked by boiling or baking. Rice flour, or legumes such as beans or lentils, a ...
. Almost all durum wheat grown in North America is spring-planted.
Winter wheat is grown throughout
Europe and
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
, and in
Siberia
Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of ...
.
Cultivation
Winter wheat is grown as a
cash crop
A cash crop or profit crop is an agricultural crop which is grown to sell for profit. It is typically purchased by parties separate from a farm. The term is used to differentiate marketed crops from staple crop (or "subsistence crop") in subsiste ...
or a
cover crop
In agriculture, cover crops are plants that are planted to cover the soil rather than for the purpose of being harvested. Cover crops manage soil erosion, soil fertility, soil quality, water, weeds, pests, diseases, biodiversity and wildlife i ...
. Optimal growing conditions for winter wheat include high-drainage soil with medium texture. Mid-quality soil nutrient content is best for winter wheat, with an appropriate supply of nitrogen being critical for the wheat to be able to establish itself in time before winter dormancy. In addition, a firm seedbed helps protect the wheat over the winter period.
Benefits of growing winter wheat
* If used as cover crop, winter wheat prevents soil erosion over winter when many fields lie fallow, and helps maintain
topsoil
* Winter wheat out-competes many weed varieties
* Can be grown as both cover crop and cash crop
* Easy to manage while still providing good yield
* Helps build soil (through heavy production of organic material) and cycle nutrients through soil
* Uses soil moisture more efficiently since it starts to grow earlier in the spring
* Crop is harvested earlier in the season, which is beneficial in regions with rainy autumn weather
United States
Winter wheat was brought to
Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to th ...
by German-
Russian Mennonites in the 19th century. Bernhard Warkentin and
Mark A. Carleton played a major part in the spread of winter wheat as a commercial crop. Warkentin organized mills in central Kansas and imported seed from
Ukraine to meet growing demand. Carleton worked for the
United States Department of Agriculture (USDA) as a crop explorer. He went to
Russia to find other wheat varieties and worked with
Kansas State University
Kansas State University (KSU, Kansas State, or K-State) is a public land-grant research university with its main campus in Manhattan, Kansas, United States. It was opened as the state's land-grant college in 1863 and was the first public insti ...
researchers to develop new ones. Winter wheat production quickly spread throughout the
Great Plains
The Great Plains (french: Grandes Plaines), sometimes simply "the Plains", is a broad expanse of flatland in North America. It is located west of the Mississippi River and east of the Rocky Mountains, much of it covered in prairie, steppe, ...
, and was, as it still is, usually grown using the techniques of
dryland farming
Dryland farming and dry farming encompass specific agricultural techniques for the non-irrigated cultivation of crops. Dryland farming is associated with drylands, areas characterized by a cool wet season (which charges the soil with virtuall ...
.
Effects of climate change
For
temperate climate
In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges througho ...
zones, increases in yields for winter wheat due to
climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...
are predicted for example in the case of spring wheat in
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by total ...
. For
Ukraine where temperatures are increasing throughout the year and precipitation is predicted to increase, winter wheat yields could increase by 20-40% in the north and northwestern regions by 2050, as compared to 2010.
[World Bank. 2021. Ukraine: Building Climate Resilience in Agriculture and Forestry. 151p.https://documents1.worldbank.org/curated/en/893671643276478711/pdf/Ukraine-Building-Climate-Resilience-in-Agriculture-and-Forestry.pdf]
References
{{Wheat
Wheat
German-Russian culture in the United States
de:Weizen#Anbau