Plant Population Formula (Plants per Acre)

This page works out plant population from spacing. Enter the distance between rows and the distance between plants in the row, both in inches; you get the plants per acre and per hectare.

Formula

Plants per acre = 6,272,640 ÷ (row spacing × in-row spacing), with both spacings in inches. 6,272,640 is the square inches in an acre (43,560 ft² × 144). Per hectare = per acre × 2.471.

Worked Example

Rows 30 in apart, plants 6 in apart.

1. Area per plant = 30 × 6 = 180 in²
2. Plants per acre = 6,272,640 ÷ 180 = 34,848
3. Per hectare = 34,848 × 2.471 = 86,111

How to read the result

This is the stand if every seed grows. To set a seeding rate, divide your target stand by the expected emergence (for example 34,848 ÷ 0.95). For twin rows or beds, use the average distance between rows.

Limits and common mistakes

• Use inches for both spacings.
• Field edges, headlands and gaps lower the real count.

Frequently Asked Questions

How many plants per acre at 30 by 6 inches?

34,848.

How many square inches in an acre?

6,272,640.

How do I find spacing for a target population?

In-row spacing = 6,272,640 ÷ (row spacing × target).

Per hectare?

Multiply plants per acre by 2.471.

in rs | Row spacing | in | 30 | 0.1 | 1000
in ps | Spacing in the row | in | 6 | 0.1 | 1000
out pa | Plants per acre | plants | 6272640 / (rs * ps) | 0
out ph | Plants per hectare | plants | pa * 2.471053815 | 0