Corn cultivation involves several critical growth stages, each requiring specific management practices to ensure a successful harvest. Here's a detailed guide on managing corn during key developmental phases:
**1. Post-Planting to Jointing Stage:**
This is a vital period for early development and setting the foundation for high yields. Proper care during this time ensures robust plant growth.
- **Temperature Control and Film Removal:** After planting, it's essential to monitor greenhouse temperatures, ideally keeping them between 25–30°C. If temperatures rise above 10°C at night, avoid opening the greenhouse to help increase the temperature difference, which promotes stronger growth. When nighttime temperatures stabilize above 12°C, remove the plastic film around mid-April (April 15–20). Be cautious of high temperatures exceeding 23°C, as they can harm young plants.
- **Trench Maintenance:** Corn is sensitive to both waterlogging and drought. Ensure proper drainage by deepening and cleaning ditches thoroughly. This helps in efficient irrigation and prevents water stress.
- **Pest Management:** After transplanting, corn is vulnerable to pests like cutworms and aphids. Use trichlorfon baits to control cutworms and apply imidacloprid to manage aphid infestations promptly.
- **Tiller Removal:** Maize is a single-ear crop, so any tillers that appear should be removed immediately. These tillers consume nutrients without producing significant yield, which could weaken the main stalk.
- **Fertilization for Strong Growth:** During the jointing stage, some plants may show signs of nutrient deficiency, such as yellowing leaves or red stems. Apply about 10 kg of urea per acre to supplement weak plants and support healthy growth.
**2. Booting to Harvest Stage:**
This phase is crucial for panicle development and grain filling.
- **Panicle Fertilization:** The best time to apply panicle fertilizer is after the jointing stage and before silking, typically when the plant has 13–14 leaves (spring sowing) or 12–13 leaves (summer sowing). Apply around 15 kg of urea per mu to enhance panicle size and grain production.
- **Ears Thinning:** After silking, multiple ears may develop on a single stalk. Remove all but the top ear to concentrate nutrients and promote larger, more uniform grains.
- **Water Management:** The booting stage is the peak period for water demand. In case of drought or high temperatures, irrigate promptly using furrow irrigation if necessary, and ensure good drainage to prevent waterlogging.
- **Insect Control:** Corn borers and aphids can reduce the quality of fresh corn, especially in summer and autumn crops. Use bio-pesticides or safe insecticides like diphtheria and imidacloprid to protect the crop without harming beneficial insects.
**3. Timely Harvest:**
For waxy corn, the optimal harvest time is approximately 25 days after pollination in spring and 22–23 days in summer. Harvest when the kernels are soft and pasty but not watery, and the silks have turned dark brown. High temperatures may speed up maturation, so regular checks are essential to ensure the best quality and flavor.
By following these management practices, farmers can maximize yield, improve quality, and ensure a profitable harvest.
*Beijing Yanjing Golden Agricultural Science and Technology Development Center*
Address: Institute of Soil Fertility, Chinese Academy of Agricultural Sciences
Shenzhen Jie Zhong Lian Investment Co., Ltd. , https://www.szmeizon.com