Plant population plays a major role in determining crop yield. Too many plants cause competition, while too few plants reduce total production. Maintaining the right number of plants per unit area is essential for achieving optimum yield in field crops.
This article explains plant population calculation in an easy and practical way.
What Is Plant Population?
Plant population is the number of plants grown per unit area, usually expressed as:
- Plants per hectare
- Plants per acre
Correct plant population ensures:
- Proper use of sunlight
- Efficient nutrient uptake
- Better air circulation
- Uniform crop growth
Why Plant Population Calculation Is Important
Accurate plant population calculation helps to:
- Decide correct spacing
- Calculate seed rate
- Improve yield potential
- Reduce crop competition
- Support scientific crop planning
Factors Affecting Plant Population
- Crop type
- Row spacing and plant spacing
- Method of sowing
- Seed germination percentage
- Soil fertility and moisture
Simple Formula for Plant Population Calculation
Formula (Per Hectare)
Plant population = 10,000 ÷ (Row spacing × Plant spacing in meters)Step-by-Step Plant Population Calculation
Example 1: Maize Crop
- Row spacing = 60 cm (0.60 m)
- Plant spacing = 25 cm (0.25 m)
Plant population = 10,000 ÷ (0.60 × 0.25)
= 66,666 plants/haPlant Population per Acre
Since:
- 1 hectare = 2.47 acres
Plants per acre = Plants per hectare ÷ 2.47
Example
66,666 ÷ 2.47 ≈ 26,990 plants/acrePlant Population Using Square Method
For crops planted at equal spacing both ways:
Formula
Plant population = 10,000 ÷ (Spacing × Spacing)
Example
- Spacing = 30 cm × 30 cm (0.30 m × 0.30 m)
10,000 ÷ (0.30 × 0.30) = 111,111 plants/haPlant Population in Broadcast Sown Crops
For broadcast crops:
- Population is estimated using seed rate and germination percentage
- Exact population is difficult to maintain
Examples:
- Rice (broadcast)
- Fodder crops
Common Plant Population for Major Field Crops
| Crop | Approximate Population (plants/ha) |
|---|---|
| Rice (transplanted) | 3–4 lakh hills |
| Wheat | 3.5–4.5 million |
| Maize | 60,000–70,000 |
| Sorghum | 1.5–2.0 lakh |
| Cotton | 10,000–15,000 |
Common Mistakes in Plant Population Calculation
- Using cm instead of meters in formula
- Ignoring germination losses
- Maintaining same spacing for all soils
- Overcrowding in fertile soils
How Agro Life Calculator Makes Plant Population Easy
Agro Life Calculator helps users:
- Enter row and plant spacing
- Instantly calculate population
- Convert hectare to acre automatically
- Avoid calculation errors
Benefits of Correct Plant Population
✔ Higher yield
✔ Better nutrient and water use
✔ Reduced pest and disease incidence
✔ Uniform crop stand
Conclusion
Plant population calculation is simple but extremely important for field crops. Maintaining the right number of plants ensures maximum yield and efficient resource use.
By understanding the basic formula or using tools like Agro Life Calculator, farmers and students can plan crops scientifically and confidently.