When to Plant Corn? A Detailed Guide to Planting Methods and Timing

Corn is an excellent grain crop and is widely grown throughout China. So, how do you grow corn? When do you plant it? Below, we introducethe planting methods and timing for corn.

I. Corn planting methods

1. Site selection

Corn is not very demanding when it comes to soil. It can be grown in loose, deep black calcareous soil, chestnut soil, and sandy loam rich in organic matter, with a pH value in the range of 6-8.

2. Seed selection

To grow corn, you first need to choose a suitable variety. According to local conditions, choose seeds with high purity, a high germination rate, and high cleanliness, and the seeds should have relatively strong lodging resistance and good disease resistance.

3. Sowing

You can sow directly by making holes in the field, then applying fertilizer and sowing. The row spacing is 65cm, the plant spacing is 18cm, and the sowing depth is 5cm. After sowing, water promptly according to the soil moisture conditions. Thin the seedlings at the 5-leaf stage, removing diseased, weak, and off-type plants and keeping vigorous ones, and fill in gaps promptly where seedlings are missing.

You can prepare the land and make beds, apply fertilizer on the surface of the beds, and make holes, sowing 2 seeds per hole. After sowing, cover with 1cm of fine soil, then build a shed over the beds. After the seedlings emerge, water with diluted manure water, and at the 5-leaf stage they can be transplanted into the field.

4. Management

(1) Temperature: Corn is a warmth-loving crop. Seed germination requires 6-10℃, and the optimum germination temperature is 28-35℃. During the seedling stage it can tolerate short periods of low temperature of -2--3℃. The jointing stage requires 15-27℃, the flowering stage requires 25-26℃, and the grain-filling stage requires 20-24℃. Early-maturing varieties require an accumulated temperature of 2000-2200℃, medium-maturing varieties 2300-2600℃, and late-maturing varieties 25OO-28OO (3000)℃.

(2) Light: Corn is a short-day plant. Under short-day conditions (8-10 hours) it can flower and set seed. According to research, corn develops quickly under short-wavelength light such as blue light during the day, and develops quickly under long-wavelength light such as red light in the morning or evening.

(3) Water: Corn has a relatively high water requirement. The most suitable precipitation during the growing period is 410—640mm. Areas with less than 150mm in summer are not suitable for growing corn. Too much rainfall affects light, increases diseases, lodging, and weed damage, and also affects the improvement of corn yield and quality.

(4) Fertilization: Apply nitrogen fertilizer as a top dressing at the jointing, booting, tasseling, and flowering and grain-filling stages. Apply 10-20kg of nitrogen per mu over the whole growth period.

(5) Cultivation and weeding: During the growth period, cultivate and earth up 2-3 times, and also remove weeds from the field.

(6) Diseases and pests: The main diseases include leaf spot, head smut, smut, black-streaked dwarf disease, and bacterial wilt, while pests include armyworm, corn borer, mole cricket, cutworm, and white grub. Attention should be paid to measures such as choosing disease-resistant varieties, strengthening cultivation management, reasonable crop rotation, and chemical control to prevent and control them promptly.

II. Corn planting time

Because corn varieties differ and growing regions differ, the planting time also differs.

For spring corn, generally from south to north, there are regions that sow spring corn from mid-February to early May, and it is generally best to sow when the temperature of the 10cm soil layer is stably above 10℃.

For autumn corn, it is usually sown from late July to early August.

In Henan, corn is planted in May.

In Hebei, spring corn is sown in late April to early May, and autumn corn must be sown no later than mid-July.

In Shandong, spring corn is generally planted in early April.

In the Northeast, corn planting time is after Guyu (around April 20).

In the South (Yangtze River Basin), spring corn is sown from late March to early April, and summer corn is sown from late May to early June.