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RedRock Grow Slab - 36 x 6 x 3 in (99 x 15 x 7.5 cm), 16 per case

In stock
Special Price $74.00 Regular Price $89.79
RedRock's commercial grade stone wool grow slab is manufactured from high-grade US made raw material. Wetting agent ensures nutrients are immediately plant available. High fiber density makes better use of water and fertilizers while allowing dry back.

RedRock Grow Slab - 36 x 6 x 3 in (99 x 15 x 7.5 cm), 16 per case

Select Grow Media for Commercial Use

RedRock's commercial grade stone wool Grow Slab is manufactured from high-grade US made raw material.

It is common to find propagators moving fresh cuttings into plugs for the initial stage of development. Once rooted plants are transplanted into stone wool grow blocks and then placed on top of grow slabs to extend root zone development and access to water and nutrients. Selecting the correct substrate for your crop depends on many variables such as size, duration, density, and more.

Propagation & Nurseries

Stone wool slabs' beneficial structure and water retention properties make them exceptionally beneficial when starting seeds and rooting propagation cuttings.

Commercial Greenhouses

Among all other properties, stone wool creates a stable growth environment for crops roots, and does not spread disease, insects and weeds.

Commercial Hydroponic

The stone wool slabs and their properties make them an indispensable product and an ideal medium for any hydroponics growing system.

Predictable Water Mobility

RedRock Wool ensures uniform movement of water and nutrients throughout the plug, block, or slab. Our products will wet-up and dry back with predictability so growers can steer crops further than ever before. New tooling and technology blend horizontal and vertical fibers for the most homogenous and predictable water transport to date.
  • Eliminates channeling and dry zones
  • Predictable water movement and nutrient availability
  • Water moves horizontally then vertically for full saturation

Pre-Cut Slabs

Automation and lower labor costs drives profits. Therefore, RedRock offers pre-cut slabs that save time and increase consistency. Pre-cut 4-Inch squares for transplanting both 4-Inch and 6-Inch blocks ensures equal plant spacing, eliminates damage during the cutting process, and less time wasted.
  • Pre-cut slabs offer huge labor savings
  • Blocks are evenly spaced across the slab
  • Custom pre-cuts are available

Tight-Fit Wrapped Slabs

Custom tailored Tight-Fit film wrap on our slabs ensure better drainage and uniform water movement across the media. Water and plant nutrition are held accessible to the root zone and forced along a straight path through the stone wool to the drainage slit(s). Additionally, we have printed tracking information on every slab to ensure cultivators can check lots for quality and consistency cycle after cycle.
  • Tight-Fit wrappers ensure nutrient rich water is plant accessible
  • Increased uniformity in water distribution
Commercial grade stone wool Grow Slabs manufactured from high-grade US made raw material.
  • Made in the USA
  • Wetting agent ensures nutrients are immediately plant available
  • High fiber density makes better use of water and fertilizers while allowing dry back
  • Exclusive Tight-Wrap packaging minimizes the liquid volume required to charge the slabs prior to planting and ensures consistent leaching of the slab for the life of the crop
  • Priced for commercial agriculture production
  • Sizes available for any crop
  • Stone wool Grow Slabs are processed in Canada


Stone wool has high moisture retention.

Nutrient Content

Stone wool has no nutrient content but will hold nutrients once treated

Oxygen Availability

97% when dry but rapidly hydrates. If allowed to drain the material allows for excellent oxygen to roots.

pH and EC

Initially has neutral pH, but can be controlled.


High. Does not decompose.

Areas of Use

Hydroponic systems ( floor and drain).


Can be sterilized and reused for couple of seasons, or shredded and used as soil conditioner.


Supports multiple crop types through all stages of growth.
More Information
Distributor Part NumberGRRR050