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Grodan Rockwool Wrapped GRO-Blocks | 4" Cube - Pack of 5 | + Twin Canaries Chart

  • Based on 109 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Saturday, Nov 30
Order within 5 hours and 57 minutes
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Description

Grodan Stonewool (rockwool) is made from molten rock spun into cotton candy- like fibers and then compressed into cubes, blocks, or slabs. Where other rockwool brand manufacturers cut all sizes from one batch of wool, Grodan is unique by making different types of fibers. The purpose is to support the requirement of the plant in the different plant stages. Grodan has a tremendous capacity for absorbing nutrient solution while retaining plenty of oxygen for rapid plant growth. Grodan comes in graduated sizes. Seedlings started in cubes are easily transferred to blocks and then onto slabs, if desired. Seedlings or cuttings started in the Grodan cubes can also be transplanted into more traditional planters and growing mediums. Grodan Blocks -Grodan Delta blocks are the most uniform blocks available on the market. They feature improved grooves at the base to promote better drainage. They are available in a large assortment of sizes and configurations to suit all types of plants. These growing blocks are used for direct sowing or "blocking on" of Macro and Multiblock raised plants. AO 36/40 plugs fit well into the hole sizes provided by the blocks. The blocks can then be placed on top of a slab to provide for a larger growing volume. It provides enough growing volume to support a larger plant, so it does not need to be placed on top of a slab.


Package Dimensions: 13.03 x 9.25 x 3.94 inches


Item Weight: 13 ounces


Manufacturer: Grodan


Is Discontinued By Manufacturer: No


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Nov 30

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Five Stars
Im just starting to put these to use. So far they appear to be your standard grodan rockwool. Edit: been using these for a while now w no issues. Make sure to soak your rockwool in low (4.0-4.5) ph water for several days and 5.8 ph with very light nutrients for 1 day prior to use or ph will skyrocket (nutrient soak is to stabilize at 5.8 and to have some starter food in the blocks). ... show more
Reviewed in the United States on September 1, 2017 by StraightUpReviews

  • They do tend to make the water a little acidic over te, best to soak and lower pH prior to using.
Perfect. Is what they say they are. And will work great for a future hydroponic holding cell for a captive plant I'll be keeping in my basement. Muah-ha-ha-ha. Thanks
Reviewed in the United States on July 28, 2019 by Sabrina Clason

  • Works as well as all their products
Works great plants growing vigorously.
Reviewed in the United States on July 10, 2021 by Kindle Customer

  • 👍
Didn't get a canary chart but blocks seem legit.
Reviewed in the United States on March 19, 2021 by Traci Fry

  • Great..customer. Service.. One..Happy.. Customer.😊😊😎
Every. Thing..look. Great..Super..fast.customer.. Service.😊😎..Thanks..
Reviewed in the United States on December 30, 2020 by Luis dominguez

  • Grossly overpriced
The product is good but this is double the price of any other online retailers
Reviewed in the United States on January 9, 2021 by Sean T L

  • thank you 😊
Had a bad experience in the beginning with the customer service but a kind man name Joseph the manager fixed the problem and I'm definitely happy with this product and him i will buy again
Reviewed in the United States on July 29, 2020 by Jaime Barrera

  • Didn’t get Canary Chart.
There were a little taller then my other 4x4 but all is well buried under hydro stones anyway.
Reviewed in the United States on May 15, 2019 by Otis Eatmon

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