Seed Calculators
Seed rate from spacing and seed quality, germination tests and seed treatment quantities.
Getting the seed rate right
Seed is one of the few inputs you can't fix later. If germination is poor or the seed rate is too low, the crop is set back from day one. If the rate is too high you waste money on seed and end up thinning or accepting a crowded stand.
The seed calculators help you buy and sow the right amount:
- Seed Rate Calculator – kilograms of seed per acre from spacing, 1000-seed weight, germination and purity.
- Germination Percentage Calculator – run a simple 100-seed test at home and adjust your seed rate to the result.
- Seed Treatment Calculator – how much treatment chemical and water you need for your seed lot, based on the dose printed on the label.
Frequently asked questions
What is test weight or 1000-seed weight?
It is the weight in grams of 1,000 seeds. It varies a lot between crops and varieties – roughly 35–50 g for wheat, 200–350 g for maize and 100–150 g for soybean. Bold-seeded varieties need a higher seed rate in kg for the same number of plants.
Should I do a germination test on certified seed?
It takes a few days and costs almost nothing, so it is worth it, especially for farm-saved seed or seed stored through a hot summer. Certified seed meets a minimum germination standard, but storage conditions can reduce it.