1Farm Background
Mr. Zhang Wei operates a 480-mu (approximately 32 hectares) corn farm in Gongzhuling, Jilin Province — one of China's premier corn-growing regions. The farm has been in continuous corn cultivation for over 15 years, supplying grain to a regional feed processing cooperative.
Despite the region's naturally fertile black soil (heitu), years of intensive monoculture had progressively depleted soil organic matter and disrupted the microbial ecosystem. By 2023, Mr. Zhang was observing declining ear weight, uneven kernel fill, and increasing susceptibility to stalk rot — all classic symptoms of soil fatigue compounded by imbalanced nutrition.
Corn field in Gongzhuling, Jilin Province — pre-treatment season
2Challenges Identified
Before designing the fertilizer program, GreenGrow's agronomist team conducted a soil analysis and field inspection in April 2024. The following problems were documented:
3GreenGrow's Customized Solution
Based on the soil analysis and crop history, GreenGrow designed a 3-product, 4-stage liquid fertilizer program. The program was formulated to address root-zone nutrition, soil biology, and foliar micronutrient delivery simultaneously.
GreenGrow R&D laboratory — formulating the Jilin corn program
Products Applied
4-Stage Application Program
4Results After One Season
At harvest in September 2024, Mr. Zhang's farm was independently assessed by the Gongzhuling Agricultural Extension Bureau. The results exceeded expectations across every measured parameter:
| Metric | Before (2023) | After (2024) |
|---|---|---|
| Grain yield | 520 kg/mu | 702 kg/mu (+35%) |
| Ear length | 18.2 cm | 21.6 cm (+19%) |
| Kernel rows per ear | 14.1 rows | 16.0 rows (+13%) |
| 100-kernel weight | 28.4 g | 33.7 g (+19%) |
| Stalk rot incidence | 12% | 3% (−75%) |
| Soil organic matter | 1.8% | 2.3% (+28%) |
| Fertilizer cost/mu | ¥185 | ¥210 (+14%) |
| Net profit/mu | ¥620 | ¥1,040 (+68%) |
"I have been growing corn for 20 years and never seen results like this. The GreenGrow team came to my farm, tested my soil, and designed a program specifically for my conditions. The yield increase paid back the fertilizer cost more than five times over. I will use this program every season from now on."
GreenGrow liquid fertilizer products used in the Jilin corn program
5Key Agronomic Learnings
Pre-planting humic acid application is the single highest-ROI intervention for degraded black soil — it multiplies the effectiveness of every subsequent nutrient application.
Zinc and boron deficiency is severely underdiagnosed in Northeast China corn. A simple soil test before planting can prevent 10–15% yield loss at minimal cost.
Liquid fertigation delivers nutrients directly to the active root zone, eliminating the 20–30% leaching loss typical of broadcast granular urea on sandy-loam soils.
Foliar micronutrient spray at tasseling is a critical insurance application — it costs less than ¥30/mu and can prevent catastrophic tip-back in hot, dry summers.
The combination of improved soil biology (via humic acid) and balanced NPK extended the effective grain-fill period by approximately 8 days, directly contributing to higher 100-kernel weight.