Use coconut coir as the best all-around medium

Coconut coir is the most recommended growing medium for microgreens. It's naturally sterile, retains moisture without waterlogging, costs less than soil, and is a renewable agricultural byproduct.

Why It Works

• Excellent moisture-to-air balance prevents the overwatering that causes mold
• Naturally free of weed seeds and pathogens (no sterilization needed)
• Fluffy texture allows excellent root growth
• Comes in compressed blocks that expand with water, saving storage space

How to Use

• Fill trays with 1-1.5 inches of pre-moistened coir
• Squeeze a handful — if a few drops come out, moisture is perfect
• Water once daily below 25°C, twice daily above 25°C

Tips

• Coir contains no nutrients, which is fine for microgreens harvested within 14 days
• A single compressed block ($15-25) fills dozens of trays
• Less than half the cost of seed-starting soil when buying in bulk