Bio Dome Planting Blocks with Sponges

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Planting Block and Bio-Sponges to Get Your Garden Growing

The revolutionary seed-starting system that has transformed the way we start seeds. Now you can start your favorite vegetables and flowers indoors, for earlier crops at a fraction of the cost of buying plants. And you can select the varieties YOU want (not the half-dozen choices the local garden center picked out), confident that with Park's Bio Dome, your seeds will sprout and your sprouts will transplant easily into the garden.

This little powerhouse from Holland bears almost no resemblance to other seed kits, which tend to produce spindly sprouts with curled-up roots and limp stems. Park's Bio Dome seedlings grow to a uniform height and width, thanks to the spacious distance between each growing cell. And our growing medium—the Bio Sponge—encourages root growth downward, NOT in an upward spiral that eventually strangles the plant. We have even enriched the sponges with oilseed extract, which gives seedlings an extra bump of nutrition.

Before and after germination, your seeds receive just as much light, water, heat, and air circulation as they need, thanks to the adjustable vents and bottom-tray watering design of Park's Bio Dome. This environment offers such great growth conditions to the emerging seedlings that Bio Dome plants are usually ready to transplant a bit quicker than other seedlings—and they suffer virtually no transplant shock in the garden. These Planting Blocks arrive complete with Bio Sponges, which need only to be immersed in lukewarm water for a few minutes to be ready for planting. Sowing seeds doesn't get any easier than this.

3 different sizes available for replacement in the Original 60-Cell, Jumbo 40-Cell, and Whopper 18-Cell Bio Domes. The blocks are inter-changeable, so if you want to expand your planting capability, it's the perfect add-on.

96601 60 cell block: L - 13¼", W - 8", H - 2¼"
96605 40 cell block: L - 13¼", W - 8¼", H - 2½"
09322 18 cell block: L - 13½", W - 6½", H - 3"

If your Planting Block is still in good condition, refill Bio Sponges are also available.


Skip Product Specs
Additional Characteristics Seed Starting
Restrictions *Due to state restrictions we cannot ship to the following:
Canada, Guam, Puerto Rico, Virgin Islands

Product Review Summary

Based on 5 reviews
The average rating for this product is 5 out of 5 stars
Overall Rating: 5.0/5.0

Customer Reviews

February 01, 2022

Repeat customer

This shopper rated the product 5 out of 5 stars

I bought the domes and inserts several years ago and have really enjoyed a variety of starts. the foam wedges are durable and easily transplantable. the polystyrene inserts also hold up to scrubbing after exposure. I have started plants for our aquariums in them and drop. works great. After 3 years I did buy a new insert, still waiting on the aftrican violets to sprout.

Pamela Bloom from FL
January 31, 2022

Kinda of pricey, but wow - they work

This shopper rated the product 5 out of 5 stars

Every year about yit his time I grumble around about the cost of these, and then wait fo a sale an d buy them. They are the best seed starting I have tried, and the 40 hole version seems to be the happy medium. I grow my zinnias, peppers, tomatoes and basil in them - the peppers and tomatoes get moved into pots as they get bigger. I wind up buying some of the foam inserts because the old ones get covered with algae if I keep the zinnias in them too long and they are hard to clean, and I run out of time. They transplant well too. And germination rates are high in these - better than other systems, plus they make it easy to control the watering. I just wish they were a little cheaper or the shipping was a little less.

Avatrix from IL
October 02, 2018

Best and Sturdiest Seed Starting System

This shopper rated the product 4 out of 5 stars

I have tried many different seed starting systems over the years, but keep coming back to Parks. It's simple, and reliable. I always have excellent germination rates with this system, even with older seed. I don't mind that the blocks take a long time to break down in the garden. I feel this adds extra water retention for the soil to both deal with excess water and help in times of drought. Would definitely give it 5 stars, except that it is a bit expensive. However, even though I try to live a somewhat frugal life, I still justify the extra expense because of the excellent results. I don't like direct sowing unless I can readily identify a very young seedling, as living in a semi-rural area, we have so many weeds that self sow in the garden even with mulching, that I don't want to risk accidentally letting a weed (especially a poisonous one such as poke weed) grow. Also, many other seed starting systems are very flimsy, but this is nice and sturdy. I have been using this system since it first started and still have some of my original blocks! One thing I do is to transplant when young and not put the blocks in the sun. That way I'm not using these containers when hardening off. Another tip, I use the blunt end of a chop stick to push the cells from the bottom when removing to prevent damage to the plant and the starter block. Base and dome are also very sturdy and have survived my hubby's rough handling (tossing here and there if he's looking for something on my work bench #!$#!). BTW, I also love the way Parks packages their seeds - keeps them viable for a long time.

K. Romer from TX
January 25, 2017

These are great

This shopper rated the product 5 out of 5 stars

I have several different sizes. I grow stocky tomato pepper and eggplant seedlings in the 40 sponge and cabbage, broccoli etc in the 60 sponge. With these sponges on the Styrofoam blocks if you will be gone for a few days you can put quite a bit of water in the tray and the block floats so the plants do not drown or get too wet and suffer damping off disease. I have a shelf with a heat mat under and 2 fluorescent shop lights over in my garage,

Delia from OR
February 19, 2014

love it love it

This shopper rated the product 5 out of 5 stars

love this bio dome because it is not to big and not to small. you can use it with out the block as well. this year i planted tomatoes tomatillos and lavender on january 2014 and today is feb 19 2014 and all of the plant are ready to go uot side. o i use 16oz water bottles cut them in half put on some seed starting mix put the seed in and i got perfec germination, In all words canot explane how great this dome is love it love it. Yuo shoud put videos on you tube of this great bio dome

joe santos from CA

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