Transplanting with RedRock Block Stonewool Grow Media

Posted on June 15, 2021 by Red Rock Block

From Plug to Slab: Transplanting With RedRock Block Stone Wool

Grow BlocksWhen starting crops, it may be a moment of reprieve once plants have been seeded and sprouts are popping up happily from the growing media. However, with the start of the growing season comes new responsibilities and duties that a grower needs to perform to ensure happy and healthy plants. From the control of the environment, watering schedules, nutrients, and transplanting a grower has many other care requirements other than starting the plants in the greenhouse. In the hydroponic realm, the operator typically grows in one of two media- either coco coir or stone wool. These both have very different properties, yet also are excellent at plant support. The number one growing media is stone wool due its ability to support plants through all stages of the growing cycle no matter how long the season.

What is Stone Wool?

Stone wool is a natural by-product of volcanic activity, its origins stemming from basaltic rock. Manufacturers of stone wool melt this volcanic rock down and spin it into thin fibers to then be pressed into specific shapes and sizes. From its start in the construction industry, stone wool has been scientifically engineered to be supportive of plant growth ever since the 1970’s. As more research and studies have been conducted, the material has shifted far from its parent material into one that is excellent for plant growth. Through this scientific research and solid data, stone wool has left its origins from the construction industry to become one of the most widely used media in the commercial horticulture industry.

Advantages of Stone Wool

Depending on the way the fibers are woven and stacked into the cubes and various shapes determines the characteristics of the product overall. These properties range from moisture retention, aeration, and moisture gradient for crops. By tweaking the density and weaving techniques, various rockwool products have been developed for specific applications. For example, one product offers drier root zones, while another allows more moisture retention. Another may offer deeper root growth, while another allows for wider and shallower root growth. The specific needs of the grower and crops need to be considered in the selection of the correct stonewool products.

In the hydroponic industry, stone wool has many advantages that make it a go to choice for the majority of commercial operations. As the material is made from molten rock and spun into plastic wrappings, this material is sterile and free of harmful pathogens such as pests, disease, and seeds from unwanted plants. Well-known brands that have been built on standards and are trusted by industry professionals such as RedRock Block, have blocks that resist decomposition and can be reused for many growing seasons unlike many other substrates used in the industry that last only one growing season.

Stone wool maintains its overall physical properties over time and over multiple growing seasons. This material is light-weight and easier to handle and shift into place until it is irrigated and filled with water- then it provides a perfectly stable environment for the plant to grow. Rockwool can be customized specific to the shape and sizes of the crops being grown. This gives the grower the ability to fully customize based on growing area and plant needs. The stone wool plugs and stone wool cubes are also able to be installed directly into larger blocks reducing transplanting stress of the plants being grown. The material is also manufactured to give the best possible moisture and aeration levels in the root zone meaning healthy and happy root growth. The material also comes ready to use off the delivery truck. This cuts time and labor needs. There are many benefits of this material and based on the needs and goals of the operation, this material may be the perfect match!

RedRock Block Stone Wool

There are many benefits that stone wool boasts, but if the stone wool does not come from a reputable source, it will not perform correctly. RedRock is a very reputable supplier of stone wool materials for the commercial operation with the home base central to Los Angeles, CA. RedRock Block is known as a supplier for some of the nation’s largest commercial greenhouses, indoor farms, commercial CEA, vertical farms, medical and research operations, and more. Commercial growers all across North America rely on RedRock Block media as a rapid supply chain delivery for the large quantities needed for the commercial operation all while still maintaining quality and standards for every stone wool product.

Features of RedRock Block’s Grow Media

Moisture High moisture retention allowing for excellent water support with a reduced risk of wilting and stunting due to water stress.
Nutrient Content Once the stone wool is treated, all stonewool blocks are able to retain and hold on to nutrients with minimal to no leaching of nutrient solution.
Oxygen Availability  Roots get a breath of fresh air with 97 percent oxygen content when dry, and with proper drainage times between waterings, excellent water and oxygen ratio for the roots.
pH and EC RedRock Stonewool has a neutral pH which means a clean slate for all plants. A grower has full control over the initial pH and EC content of the media allowing for full customization based on individual crop needs.

Transplanting Ease with RedRock

One of the biggest stressors in a greenhouse that is not environmentally caused is by transplanting. Although transplanting causes stress on a plant that can cause slight delays in growth for a short period of time, it is a required practice as a grower graduates plants into larger growing areas. The largest benefit of stone wool is the ability to transplant a crop without disrupting the root zone! With RedRock stone wool, the plugs and cubes are shaped and designed to fit right into larger blocks and slabs through simple placement into either pre-cut or self-cut holes. Stone wool material allows for roots to grow out the bottom and around one placed into larger stone wool material. Traditional transplanting required handling both the stem and root zones. This can also cause breakage of leaves and roots alike. With RedRock Block’s stone wool, a plant has no disturbance in the root zone risking precious roots. All slabs can be custom sized and shaped specific to the operation needs or a grower can select from prefabricated slabs and cubes.

Brief Listing of Stone Wool Products Offered (Click Links to Product Pages)

Product  Sizing
Starter Plugs (Standard and Pro Series) Loose Bundles
Starter Cubes and Starter Blocks 4”x4”x4” , 4”x4”x2.5”
Grow Block (Standard and Pro Series) Standard:

4’’x4’’x4’’, 6’’x6’’x5.3’’


6’’x6’’x5.3’’ , 4’’x4’’x2.5’’

Grow Slab 36’’x6’’x3’’
Flowering Slab 12’’x8’’x4’’

Shop RedRock Block Premium and Pro Lines of Stonewool Grow Media

RedRock Blocks offers high quality, commercial grade stone wool plugs, starter blocks, grow cubes, grow blocks, and grow slab manufacturer based out of Los Angeles, California. RedRock Block supplies some of the nation’s largest commercial greenhouses, indoor farms, commercial CEA and hydroponic operations, vertical farms, medical and research grow ops, along with many other types of CEA facilities.


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