Grodan Grow-Cubes, 5.3 cu ft (loose in box)

Loose Stone Wool Growing Cubes for Custom Fill Applications, 5.3 cu ft, Bulk Box

Some propagation and growing setups call for loose stone wool rather than pre-formed blocks or slabs, whether to fill custom containers, top-dress an existing medium, or blend into another substrate. Grodan Grow-Cubes package the company's stone wool fiber technology in loose cube form for exactly that kind of custom-fill use.

This 5.3 cu ft size ships loose in a bulk box, suited to larger operations filling many containers.

Key Features & Benefits

• Loose cube format — fills custom containers or blends into another growing medium rather than a pre-formed block shape.
• Chemically inert stone wool — doesn't alter the pH or nutrient balance of the feed solution.
• Consistent fiber structure — the same engineered stonewool fiber technology used across Grodan's block and slab lines.
• Bulk and retail packaging — available as a smaller retail bag or a larger bulk box depending on volume needed.

Who Should Use Grow-Cubes

Growers filling custom containers, blending stone wool into another substrate, or top-dressing an existing medium, rather than using a pre-formed block or slab shape, are the best fit for loose Grow-Cubes.

About Grodan

Grodan pioneered engineered stone wool growing media in 1969 and operates today as part of ROCKWOOL Group. Grow-Cubes package the same fiber technology used across the company's block and slab lines in a loose, custom-fill format.

Frequently Asked Questions

What is the loose cube format used for?

Grow-Cubes are meant for custom-fill applications, such as filling a non-standard container, blending into another growing medium, or top-dressing an existing setup, rather than functioning as a pre-formed block or slab. Growers choose the loose format specifically when a fixed block shape doesn't fit their container or workflow.

How much volume comes in each size?

The smaller size ships as a 2 cu ft retail bag, while the larger size ships as a 5.3 cu ft bulk box. Matching volume to your container count avoids over- or under-ordering for a specific fill job.

Is loose stone wool chemically inert like Grodan's blocks and slabs?

Yes, it uses the same chemically inert stone wool fiber as Grodan's block and slab lines, so it won't alter the pH or nutrient balance of the feed solution. Growers control the root zone through their nutrient program rather than through the media.

Can Grow-Cubes be blended with another growing medium?

Yes, the loose cube format is suited to blending into another substrate, unlike a pre-formed block or slab that has to be used as its own standalone unit. This makes it a flexible option for growers customizing their own mix.

Does the cube size affect performance?

The cube size affects handling and fill volume more than fundamental performance, since both sizes use the same fiber technology. Choose based on the volume of loose fill your setup needs rather than a performance difference between the two.