Peat Pellets seed starters are high quality, compressed peat pellets with added low-ammonia fertilizer encased in a thin biodegradable mesh netting. They expand to 7 times their original size just minutes after water has been added. They are ideal for starting most small-seeded plants, from flowers to lettuce, basil to quinoa. Jiffy peat pellets make for very uniform seedling pots. Healthy young plants mean healthy finished plants. These make a fun introduction to young kids as they expand in water so quickly, and then seem to sprout like magic. Be sure to keep seeded pellets moist by misting or watering from the bottom. Transplant the complete seedling, pellet and all, when the soil is warm enough. Each dry pellet measures 40mm in diameter.