Microgreens Seed Calculator
Calculate Exactly How Much Seed You Need for Any Tray Size
Stop guessing how much seed to buy and start calculating exactly what you need. Select your microgreens variety, choose your tray size, enter the number of trays, and get the precise seed amount in grams and ounces plus the expected yield at harvest. Seed density rates are based on standard commercial growing rates used by professional microgreens producers.
Select your microgreen variety, tray size, and number of trays to calculate exactly how much seed you need and what yield to expect at harvest. All seed density and yield data is based on standard commercial growing rates.Microgreens Seed Calculator
HOW TO USE THE CALCULATOR
- Select your variety. Choose from 35 microgreens varieties organized by category. When you select a variety the calculator immediately shows the seed density rate, whether pre-soaking is required, days to harvest, and difficulty level for that variety.
- Select your tray size. Choose from 10×20 standard tray, 10×10 half tray, 5×5 quarter tray, or enter a custom size in inches.
- Select number of trays. Choose from 1 to 50 trays.
- Click Calculate. Get total seed needed in grams and ounces, seed per tray, total grow area, expected yield per tray and total, and complete growing notes for your selected variety.
- Download your results. Save your calculation as TXT, PDF, or Word.
UNDERSTANDING SEED DENSITY
Seed density is the weight of seed needed per square inch of tray surface. Different microgreens varieties have very different seed sizes and therefore very different seeding rates. Large seeds like sunflower and peas require much more seed per tray than tiny seeds like broccoli or arugula.
The density rates in this calculator are based on commercial growing standards used by professional microgreens producers. Home growers can use the same rates for consistent and predictable results.
Why Density Matters
Too little seed results in sparse uneven growth that does not fill the tray. Too much seed leads to overcrowding, poor airflow, mold problems, and weak spindly growth. The correct density for each variety is calibrated to give full dense even coverage without the problems that come from overcrowding.
TRAY SIZE GUIDE
- 10×20 Standard Tray (200 sq in). The industry standard tray used by most commercial microgreens producers. Produces the most product per tray and is the best choice for anyone selling or producing volume.
- 10×10 Half Tray (100 sq in). Half the area of the standard tray. Good for home growers wanting variety without the volume of full trays.
- 5×5 Quarter Tray (25 sq in). Ideal for trying a new variety before committing to larger production. Great for kitchen windowsill growing.
- Custom Size. Enter any dimensions for non-standard containers or growing systems.
SOAKING AND GERMINATION
Many microgreens varieties benefit from pre-soaking before planting. Large seeds like sunflower, peas, and fava beans absorb water and begin the germination process during soaking which results in faster and more even germination after planting.
Some varieties have mucilaginous seeds that become gel-like when wet. Basil, arugula, flax, chia, and cress fall into this category. These varieties should NEVER be soaked in water as the seeds will clump together in a solid mass. The calculator notes which varieties are mucilaginous and require special handling.
EXPECTED YIELD
The yield calculation estimates harvest weight based on the seed weight planted multiplied by the expected yield ratio for each variety. Actual yields will vary based on growing conditions including light, temperature, humidity, growing medium, and harvesting timing. The calculator provides a reliable estimate for planning purposes.
Most microgreens yield 1 to 2.5 times the weight of seed planted. Large seeded varieties like peas and fava beans have the highest yield ratios. Small seeded herbs like basil and celery have lower yield ratios but command premium prices at market.
FREQUENTLY ASKED QUESTIONS
Are these seed rates for commercial or home growing?
Both. The seed density rates are based on commercial standards which work equally well for home growers. Professional growers use the same rates for consistent results.
What growing medium should I use?
Most microgreens grow well in a quality potting mix, coconut coir, or hydroponic grow pads. The calculator assumes soil or coir-based growing. Hydroponic growing may require slightly different density rates.
Can I use this for sprouts instead of microgreens?
No. Sprouts are grown without any growing medium in mason jars and have completely different seed quantities. Use our Sprouting Guide for sprouting calculations.
Is this tool free?
Yes, completely free with no account required.
OTHER FREE TOOLS
- Sprouting Guide: Mason jar sprouting guide for 36 varieties. thegardenerstoolbox.com/sprouting-guide
- Seed Starting Database: Complete seed starting guide for 50 varieties. thegardenerstoolbox.com/seed-starting-database
- Companion Planting Guide: Good and bad plant neighbors. thegardenerstoolbox.com/companion-planting-guide
- Canning and Preservation Guide: USDA approved home canning times. thegardenerstoolbox.com/canning-preservation-guide