Microgreens Seeding & Seed & Yield per Tray

Microgreens are young vegetable and herb seedlings sown densely, grown for just 7–12 days, and harvested at the first true leaves. They pack intense flavour and colour into a fast, high-value crop you can grow indoors on shelves — making them one of the quickest ways to turn a little seed and space into saleable produce.

Total seed = trays × seed per tray. You set the seed rate per tray for the crop you are growing, and the tool multiplies it by the number of trays you plan to sow. For example 20 trays of radish at 30 g per tray needs 600 g of seed — handy for ordering the right amount before a sowing run.

Fresh harvest = total seed × yield ratio, where the yield ratio is the weight of fresh microgreens you get per unit of seed. Radish runs about 10× (a strong, vigorous crop) while pea sits nearer 6×. Multiply the seed sown by that ratio to estimate the kilograms of cut greens you can expect.

It varies by crop and tray size. Fast, large-seeded crops like radish are sown around 30 g per standard 10×20 tray; smaller seeds go lighter, while pea and sunflower are sown much heavier at roughly 80 g per tray. Start from a known rate, then fine-tune to avoid both bald patches and damp, mould-prone overcrowding.

The yield ratio is fresh harvest weight divided by seed weight. It captures how productive a crop is — radish around 10×, pea around 6× — and depends on variety, light, temperature and how you grow. Track your own trays a few times and use your measured ratio for the most accurate planning.

Big, hard seeds like pea, sunflower and beet germinate faster and more evenly after an 8–12 hour soak, which kick-starts the crop and shortens the cycle. Small seeds such as broccoli, radish and cabbage don't need soaking and are simply spread dry across the moist medium.

Stagger your sowings — start a few trays every couple of days rather than all at once — so trays mature in a rolling sequence and you always have fresh greens to cut. The calculator helps size each batch; pair it with a sowing schedule so your harvest matches what you can sell or eat each day.

Most are ready in 7–12 days from sowing to harvest, cut at the first true leaves when flavour and colour peak. Fast crops like radish can be done in about a week; slower ones such as basil take longer. The short cycle is what makes microgreens a quick-turnaround, high-value crop.

Yes — enter the seed rate per tray for your crop and tray, and the yield ratio you expect, and the tool scales to any number of trays. Whether you grow radish, pea, sunflower, broccoli or a mix, just use the right per-tray figures for each and it gives the seed and harvest.

They're solid planning figures. Real seed rates and yields shift with variety, seed quality, light, temperature, humidity and growing medium, so treat the outputs as a starting point. Measure a few of your own trays, refine your seed rate and yield ratio, and the estimates will track your operation closely.