Pargro Rockwool Slab | 36in x 6in x 4in with (3) 10x10 Precut Holes - Bag

Precut Rockwool Slab for Uniform Irrigation, 36x6x4in

Handling dozens of slabs across a room only stays manageable when each one behaves the same way under irrigation. Pargro Rockwool Slab is built with a consistent internal structure so water distributes uniformly and setup stays predictable slab to slab.

36in x 6in x 4in slab, 3 precut 10x10 holes, bag, 12/carton.

Key Features & Benefits

• 36in x 6in x 4in slab with 3 precut 10x10 holes — ready-to-plant sizing for standard transplant blocks.
• Consistent slab structure — supports predictable handling and setup across a full carton.
• Sold in a bag, 12 per carton — sized for growers outfitting multiple rows or a full room.
• Built for precise irrigation and nutrient management — supports uniform water distribution across the slab.

Who Should Use the Pargro Rockwool Slab (36x6x4in)

This fits growers outfitting multiple rows or a full room who want precut, consistently structured slabs sold by the carton, and who have confirmed the 4in depth fits their tray or drip setup.

About Grodan the Pargro Rockwool Slab

the Pargro Rockwool Slab is manufactured using Grodan's stonewool process, in which molten rock is spun into fibers and compressed into a consistent, sterile growing medium, a method the brand applies across its full propagation and slab lineup.

Frequently Asked Questions

How many holes does the Pargro Rockwool Slab have?

It comes with three precut 10in x 10in holes across a 36in x 6in x 4in slab, spaced for standard transplant blocks. The precut sizing removes the need to cut holes before planting.

How is this slab packaged?

Each slab ships in a bag, with 12 bags to a carton, sized for growers setting up multiple rows or a full room at once. That carton count makes it practical to order in bulk for larger operations.

What does 'consistent structure' mean for handling this slab?

Pargro Slabs are built with a consistent internal structure so each slab handles predictably and supports uniform water distribution across its length. That consistency matters when growers are setting dozens of slabs on the same irrigation schedule.

How does this compare to Grodan's Improved Gro-Slab?

Both are precut rockwool slabs with three 10in x 10in holes, but Pargro is a separate Grodan sub-brand from the Improved Gro-Slab line and, per this listing, ships one inch deeper at 4in versus the Gro-Slab's 3in. Growers should confirm depth against their tray or drip setup before ordering.