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Plant 2 New Crops of Jumbo Seedlings with these 80 Bio Sponges!

80 Pack Refill Sponges for the 40-cell Planting Block

Pack of 80
Item # 06452-PK-80
$24.95
Buy 2+ at $22.95 ea
Available to ship.

Just soak them in water for a few minutes, then fit them into the Bio Planting Block!

This rooting medium is intended for use with Park's 40-Cell Jumbo Bio Planting Block
Your Jumbo Bio Planting Block will last a lifetime with these handy, economical Bio Sponges! You get 80 sponges in this refill kit, enough to fill not one but two Bio Domes, or one Whopper Dome!

When you're ready to begin a new crop in the Planting Block, first be sure that the styrofoam block has been thoroughly disinfected (warm water with a splash of bleach is fine). Then soak 40 of the Jumbo Bio Sponges in warm water for a few minutes. They expand, revealing the pre-drilled planting hole at one end. Simply slip one seed into the hole of each Bio Sponge, place the Sponge seed-side-up in the cell of the Planting Block, and you're on your way to another bumper crop of healthy, strong, super-quick seedlings!

You can also purchase a replacement 40 Cell Jumbo Bio Planting Block and 40 Bio Sponges.

ItemForm Pack of 80
Size 40-cell (Pack of 80)
AdditionalCharacteristics Seed Starting
Restrictions Canada, Guam, Puerto Rico, Virgin Islands
Overall Rating: 5 Stars
Average Based on 1 Reviews Write a Review
Believe your eyes
Lower Forty Gardener from GA wrote (February 05, 2013):
You will never find a better way to start transplants. I have used these now for the last two gardens. I grow in containers and I am able to plant 8 pepper plants in one grow box. I grew all of my own transplants for about $20 and they would have cost me over $110. My transplants are healthier, and have incredible root systems that provide excellent plants. I use these for tomatoes, cucumbers, bell peppers, okra, squash, and herbs. They are no problem.

What are the differences between the various Bio Domes: 60-cell, 40-cell, and 18-cell?

The original 60-cell Bio Dome has a 60-cell planting block with 60 Bio Sponges and will produce 60 plants at one time. The 1" wide by 2 ¼" deep cells are larger than average, and a spacious 1 3/8" apart. The bio-sponges are the same size as the cells; 1" wide by 2 1/4" deep. You can grow and keep plants in the 60-cell bio-dome for 6-8 weeks before transplanting. Many varieties will just need 6 weeks until transplanting. Tomatoes and peppers would appreciate the full 8 weeks before transplanting. So, the original 60-cell bio-dome would be great for starting all of your favorite vegetable and flower seeds, with a larger number of plants produced at one time.

The 40-cell Bio Dome has a 40-cell jumbo planting block with 40 Bio Sponges and will produce 40 plants at one time. The cells are wider and deeper than the original 60-cell planting block and provide good spacing to maximize air flow. The cells are 1 1/4" wide by 2 1/2" deep. The Bio Sponges are also 1 1/4" wide by 2 1/2" deep. You can grow and keep plants in the 40-cell bio-dome for at least 6-8 weeks and some for up to 9-10 weeks, because of the wider spacing and cell/sponge size. It too would be excellent for starting all your favorite vegetable and flower seeds, with the added benefit of giving more room and time for larger plant development.

The 18-cell Bio Dome has an 18-cell whopper planting block with 18 Bio Sponges and will produce 18 plants at one time. It has the largest cells of any of the Bio Domes we offer and is great for growing extra-stocky transplants and even for rooting cuttings. The cells are 3" tall by 1 3/4" wide. The Bio Sponges are also 3" tall by 1 3/4" wide. You can grow and keep plants in the 18-cell Bio Dome for at least 8-10 weeks and some for up to 12 weeks, giving the maximum amount of growing time and spacing between plants as compared to the 60-cell and 40-cell Bio Domes. If you are looking to grow your favorite vegetable and flower seeds into large, stocky transplants for setting out in spring, then the 18-cell Bio Dome is the one you want to buy. It would be excellent for growing Tomatoes and Peppers.

How much water should be put in the Bio Dome and how often?

The beauty of the Bio Dome is that you cannot overwater! You just keep water in the tray and float the block. The larger the seedlings get, the more water they will use and you will need to add water more frequently as they grow. Initially, during germination, you may not have to water as frequently, because minimal water is being used and Bio Sponges will stay moist longer, so you may only have to water once every 1-2 weeks. Later, as plants grow and water use is greater, depending on the room temperature and the amount of light received, you may have to water more often -- possibly 1-2 times a week -- or as often as required to keep the sponges moist.