Plant Spacing & Population & Seed Calculator
Calculates plants per acre
Enter your row and plant spacing and field area to get the exact plant population per acre and hectare — and how many seeds to buy after germination losses.
Plan for 33,724 plants on your 1 acre (33,724/acre). Buy about 37,472 seeds — roughly 11% extra to cover 90% germination, so gaps don't cost you a thinner stand.
Tip: a triangular (staggered) layout at the same spacing fits about 15% more plants in the same field.
Next: confirm the recommended spacing for your variety, then check the right sowing window in the crop calendar before buying seed.
Spacing & population — key facts
- Formula
- Plants = area ÷ (row × plant spacing)
- 1 acre
- 4,046.86 m²
- 60×20 cm on 1 acre
- ≈ 33,724 plants
- Triangular layout
- ≈ +15.5% plants vs square
- Seeds to buy
- plants × seeds/hole ÷ germination%
- Units
- acre · hectare · bigha · guntha · m² · ft²
- Presets
- Tomato, maize, potato, onion + more
- Privacy
- Runs in your browser; nothing uploaded
How plant population is calculated
Each plant occupies a small rectangle of ground equal to its row spacing × plant spacing. Convert that to square metres, and the number of plants is simply your field's area divided by that per-plant area. So at 60 × 20 cm each plant takes 0.12 m², and one acre (4,046.86 m²) holds about 33,724 plants. A triangular layout staggers alternate rows so plants nest in the gaps, fitting roughly 15.5% more in the same space.
Because some seed never germinates, you must buy more seed than your target population: divide by the germination rate (and multiply by seeds per hole if you sow more than one). This calculator combines all of it so you order the right amount the first time.
Plants per acre calculator
Get the exact plant population per acre for any row × plant spacing — the number that drives your seed order and expected yield.
Seeds needed for a field
Turn your target population into a seed quantity, adjusted for germination rate and seeds per hole, so you never under- or over-buy.
Triangular vs square planting
Compare layouts instantly: triangular spacing fits ~15% more plants at the same distance for higher density crops.
Crop spacing presets
One tap loads typical spacing for tomato, maize, potato, onion, cotton, sugarcane and more — then fine-tune for your variety.
Frequently Asked Questions
How do I calculate plants per acre?+
Divide the area of one acre (4,046.86 m²) by the area each plant occupies (row spacing × plant spacing in metres). For example, at 60 × 20 cm that's 0.6 × 0.2 = 0.12 m² per plant, so 4,046.86 ÷ 0.12 ≈ 33,724 plants per acre. This tool does it for any spacing, area and unit.
How many seeds do I need for my field?+
Take the plant population, multiply by the seeds you sow per hole, then divide by the germination rate. At 90% germination and 1 seed per hole you buy about 11% more seed than plants; at 2 seeds per hole, more again. The calculator shows the exact seed quantity.
What is the formula for plant population?+
Plant population = field area ÷ (row spacing × plant spacing), with all areas in the same units. Convert centimetres to metres first, then divide the field's square metres by the per-plant square metres.
Does triangular spacing fit more plants than square spacing?+
Yes — a triangular (staggered or hexagonal) layout packs about 15.5% more plants into the same area at the same spacing, because each plant sits in the gap between two plants in the next row. Switch the layout toggle to compare.
What is the best spacing for tomato / maize / potato?+
Common field spacings are tomato ~90 × 45 cm, maize ~60 × 20 cm, potato ~60 × 20 cm and onion ~15 × 10 cm. Use the crop preset chips to load these, then adjust for your variety. Exact spacing depends on variety, irrigation and mechanisation.
How do I account for germination rate?+
Set the germination percentage from your seed packet or a quick germination test. The calculator divides the required plants by that rate, so you buy enough seed to still reach your target stand after some seeds fail to sprout.
Can I use acres, hectares or bigha?+
Yes — pick acre, hectare, bigha, guntha, square metres or square feet. Note that bigha varies by region; this tool uses a common North-India pucca bigha (≈2,529 m²), so adjust if your local bigha differs.
Why does spacing matter for yield?+
Too few plants wastes land and light; too many causes competition for water, nutrients and light, smaller plants and more disease. The right population for your crop and conditions is one of the biggest levers on yield per acre.
How do I convert plant population to seed rate by weight?+
Multiply the seed count by the weight of 1,000 seeds (the thousand-grain weight) and divide by 1,000 to get kilograms. This tool gives the seed count; combine it with your seed's TGW for kg per acre.
Is closer spacing always better?+
No. Beyond the optimum, closer spacing reduces individual plant size and can cut total marketable yield and quality while raising seed cost and disease pressure. Aim for the recommended population for your crop, not the maximum.