Pre-drilled planting holes for easy seed insertion, saving time and effort
Enriched with oilseed extract to provide extra nutrition for seedlings
Made from coconut coir, peat moss, and bio char for optimal moisture retention
Available in three different sizes to fit various Bio Dome blocks
Reusable and durable design ensures long-lasting use
Summarized by Shop
Your Bio Planting Block will last a lifetime with these handy, economical Bio Sponges. When you're ready to begin a new crop in the Planting Block, first be sure that the block has been thoroughly disinfected (warm water with a splash of bleach is fine). Then soak the Bio Sponges you intend to use in warm water for a few minutes. They exp
Material
Coconut coir, peat moss, bio char
Enrichment
Oilseed extract
Sizes
Three available
Compatibility
For use with Bio Dome seed starting blocks
Reusable
Yes
Summarized by Shop
5.0
14 ratings
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1
Still getting use to using them. Not fully impressed yet.
S
Spencer · August 14, 2026
These sponges, along with Park's Bio-Dome, are ideal for germinating seeds. I planted a variety of clover there, and I saw germination starting overnight. Of course, most seeds need more time and care before they germinate, but Park's system provides the right combination of air and moisture for the seeds, and for their growth into strong seedlings for planting.
Wendy Lou · April 17, 2026
Nicely packaged, moist, and fit perfectly in my Aerogarden Starter Tray. Will buy again.