When is the best time to harvest wheat?
The best time to harvest wheat is when the wheat is at nine-tenths maturity, not when it is at ten-tenths maturity; that is to say, the wheat's wax-ripening stage is the best time to harvest. You may have all heard this saying, but what is the science behind it? Let's take a look below.
What are the characteristics of the wheat wax-ripening stage?
1. Grain. The grain is generally orange-yellow in varying shades of light and dark. After cutting with a small knife, the cross-section appears waxy and slightly hard, with only the ventral groove slightly soft. The empty cavity near the ventral groove has disappeared, and the back of the grain can still be pressed to leave a slight fingernail mark.
2. Leaf tips, leaves, and leaf sheaths of the wheat plant. The leaf tips, leaves, and leaf sheaths of the wheat plant turn yellow in sequence, and the stem turns yellow from bottom to top. Only the upper leaf and its vicinity remain green. The stem below the ear turns yellow. The flag leaf sheath and the second node from the top turn yellow but do not dry up. The whole plant shows three sections: yellow, green, yellow.
3. Wheat field. When observing the wheat field from a distance, if the wheat plants are yellow at both top and bottom with a green band in the middle, you can conclude that this wheat field has entered the wax-ripening stage, and this is the most suitable time for harvesting.
Why should wheat be harvested in the middle and late wax-ripening stages?
In the early wax-ripening stage of wheat, the grain begins to harden, and the grain also slowly hardens from a milky state. If you take out a wheat grain and scratch it with your fingernail, it will appear waxy.
By the middle wax-ripening stage of wheat, the whole wheat plant turns withered yellow, but the wheat stem still has elasticity. This is the best time for manual harvesting.
At the late wax-ripening stage of wheat, the accumulation of dry matter in the wheat grain reaches its peak, the quality is good, the yield is the highest, and the plant is also physiologically fully mature. This is generally 2-3 days earlier than the full-ripening stage (when the wheat grains become completely hard), and this is the best time for machine harvesting.
Why not wait until the full-ripening stage of wheat to harvest?
Nowadays, most wheat fields are harvested by machine, and some farmers wait until the full-ripening stage of wheat to harvest.
When wheat grows to the full-ripening stage, the wheat stem is completely dry, the grain volume shrinks, the moisture content decreases, and the grain becomes dry and hard, not easily crushed when pressed with a fingernail. At this time, mechanical harvesting threshes easily and does not easily break the grain. However, at the full-ripening stage, the wheat stem, straw, leaves, and roots can no longer manufacture and accumulate nutrients, but they still need to consume nutrients for respiration. Nutrients from the grain flow back into the straw, causing grain weight to decrease, and yield per mu will be reduced by 30 kg to 50 kg.
In addition, if continuous rainy weather occurs at this time, the wheat is prone to sprouting and molding, the quality deteriorates, and the loss is even greater. Therefore, grasping the harvest timing and harvesting in good time is very important. Do not wait until the wheat is so mature that the grains fall off by themselves before harvesting. By then, the yield reduction will not just be a matter of harvesting 100 jin less.
Wheat harvesting time:
The best times of day for wheat harvesting: 9:00-11:00; 16:00-18:00
Nowadays, combine harvesters are basically used for the work, so choose the above two time periods.
Before 9:00, the dew on the wheat stalks has not completely evaporated; from 11:00-16:00, the weather is too hot and the wheat stalks are dry; after 18:00, dew gradually begins to form.
During these two time periods, the wheat is not damp and threshes easily; and it is not too dry. If the wheat stalks are too dry, the wheat grains can easily burst open by themselves, making it hard to get every grain into the granary.