How do I calculate how much seed to order?

Heirloom works it out from your plan, so you order the right amount without a spreadsheet or a calculator. Each planting knows how many seeds it needs, and the Seeds Inventory adds them up for the season in Season needs.

To get grams or ounces instead of a seed count, give each cultivar its seed weight: a Thousand-seed weight or a number of Seeds per unit, in its window in the Crop Library. Without a weight, Heirloom can count seeds but not weigh them.

The steps are in Add and adjust cultivars.