browsef 20230907 Grodan Rockwool Wrapped GRO-Blocks | 4″ Cube – Pack of 5 | + Twin Canaries Chart

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

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

Grodan Rockwool Wrapped GRO-Blocks

Grodan Stonewool (rockwool) is made from molten rock spun into cotton candy-like fibers and then compressed into cubes, blocks, or slabs. Unlike other rockwool brands, Grodan uses different types of fibers to support the requirements of plants in different stages of growth. The unique composition of Grodan allows for excellent absorption of nutrient solution while retaining ample oxygen for rapid plant growth.

Features and Benefits

Uniformity and Drainage

Grodan Delta blocks are the most uniform blocks available on the market. They feature improved grooves at the base to promote better drainage, preventing “wet feet” for your plants. The gro-block holes are the perfect size for any 1.5″ Starter plug or macroplug, making it easy to transfer seedlings or cuttings. The bases of the gro-blocks are grooved to promote drainage and avoid waterlogging.


Grodan Blocks come in a variety of sizes and configurations to suit all types of plants. Whether you’re direct sowing or “blocking on” raised plants, these growing blocks provide enough volume to support larger plants. They can be placed on top of a slab to create a larger growing space, eliminating the need for a larger slab.

Easy Transplantation

Seedlings started in Grodan cubes can be easily transferred to blocks and then onto slabs, if desired. Alternatively, they can be transplanted into more traditional planters and growing mediums. The flexibility of Grodan allows for seamless transplantation and ensures the healthy growth of your plants.

Frequently Asked Questions

1. Can I use Grodan Blocks for all types of plants?

Yes, Grodan Blocks are suitable for a wide range of plants. They provide ample growing volume and can support the growth of larger plants.

2. How do I use the Twin Canaries Liquid Volume Conversion Chart?

The Twin Canaries Liquid Volume Conversion Chart is included with the Grodan Rockwool Wrapped GRO-Blocks. It helps you convert liquid volumes accurately, ensuring precise nutrient solution measurements for your plants.


Grodan Rockwool Wrapped GRO-Blocks are the perfect choice for plant growth. With their unique composition, excellent absorption capabilities, and versatile design, these 4″ cubes provide optimal conditions for your plants. Say goodbye to inconsistent growth and hello to healthy, thriving plants with Grodan.