How much seed do I actually need per acre and why does it vary?

Seed rate is not a single fixed number; it depends on the crop, seed size, germination percentage, spacing, sowing method and sowing time. Bold (large) seed of the same crop needs more weight per acre than small seed for the same plant count. If germination is below 85 to 90 percent, you increase the rate to make up for the seeds that will not come up. Broadcasting needs more seed than line sowing with a seed drill, and late sowing of crops like wheat needs a higher rate to compensate for fewer tillers. The honest method is to fix your target plant population per acre and work backwards using the test (germination) weight. As broad ranges only, hybrids of vegetables and cotton need very little seed per acre, cereals like wheat need a moderate bag-level quantity, and bold pulses need more by weight. Because the exact figure changes with variety and conditions, confirm the recommended seed rate for your specific crop and variety with your KVK or the agriculture department.