Seed Starting & Propagation Calculators

Which seed starting calculator do you need?

• Seed Tape Length & Seed Count Calculator: How much seed tape to make and how many seeds to glue on for your rows.
• Seedling Shelf & Tray Capacity Calculator: How many seed trays and cells fit on your grow shelf, tier by tier.
• Seed Starting Mix Batch Calculator: How much seed-starting mix fills your cell trays, split into a homemade recipe.
• Cutting Propagation Batch Calculator: How many cuttings, donor plants and trays you need to end up with a target number of plants.
• Seedling Pot-Up Soil Calculator: Potting mix, pots and carry trays for potting on a batch of seedlings.
• Bulb & Corm Planting Quantity Calculator: How many tulip, daffodil or crocus bulbs fill a bed, with planting depth and packs to buy.
• Microgreens Tray & Seed Calculator: Trays to sow each week and seed to buy for a steady supply of microgreens.
• Seed Calculator: How many seeds and packets to buy for the plants or rows you want, allowing for germination.
• Seed Germination Calculator: Your germination rate from a paper-towel test, and how many seeds to sow per plant.
• Seed Rate Calculator: Seeding rate by weight from target plants, thousand-seed weight, germination and establishment.

Every tool works in metric or imperial units, shows its formula and a worked example, and lets you edit the assumptions that vary from garden to garden. Results stay on your device; nothing you enter is stored.