Hortiblock 128 Cells Square

The Hortiblock 128 Cells Square is a reusable, food-grade expanded polystyrene seed-starting tray with individual square cells that virtually eliminate transplant shock. When the tray bottom is exposed to air, the taproot is air-pruned so feeder roots grow downward instead of spiraling, letting plants start growing immediately after transplanting.

At a glance

• Type: Reusable seed-starting tray
• Material: Food-grade expanded polystyrene
• Cells: 128 square cells, 1.375" square x 2.5" deep
• Drainage: 0.375" drain hole per cell
• Tray size: 26-1/2" x 13-1/2" overall
• Reusable: Lasts many years

Best for

• Starting transplants with strong root systems
• Air-pruning to prevent root spiraling
• Clean, shock-free transplanting
• Avoiding spread of root pests and diseases
• Repeated seasonal reuse

How to use

Fill the square cells with starting mix and sow seed, keeping the tray bottom exposed to air so taproots air-prune. At transplant time, the plant, soil, and undamaged roots pop out cleanly without tearing or tangling, so seedlings establish quickly. Rinse and reuse the tray for many seasons.

About Grow Organic

Grow Organic (Peaceful Valley Farm and Garden Supply) has served organic gardeners since 1976 with seeds, amendments, and tools selected for sustainable, productive growing.