Grodan Macro Plugs with Slit | 1.5 in Round Stone Wool Clone Plugs, 2,000

Grodan Macro Plugs, Round and Slit for Cuttings

Each Macroplug is a loose round stone wool plug, 1.5 in across and 1.57 in tall, with a slit cut down through the top. The slit opens to take a cutting stem, then closes around it so the base sits in firm, even contact with the fibre. Seeds work as well, dropped into the same opening. This bulk case holds 2,000 plugs and measures about 23.0 x 18.1 x 23.3 in at 18 lb. The fibres run predominantly vertical, which gives each plug the spring to hold its shape when handled. A balance of small and large pores keeps air and water together throughout the plug. Every plug carries the same density and firmness, so water, nutrients and pH spread evenly from one to the next. Condition them in a balanced nutrient solution at an EC of at least 1.5 mS/cm and a pH of 5.5 to 6.5. Soak them for several minutes or saturate them overhead in several passes, then let them drain. Set each plug into its own cell before the cutting goes in.

Rockwool Clone Plugs Built to Drop Into a Gro-Block

That last step matters more than it looks. A loose round plug in an open tray can spread at the slit, but an individual cell holds it closed around the stem. Keep cuttings humid early on, and vent the dome a little more each day as roots appear. Weigh trays at the start and use the weight loss to time irrigation, since stone wool holds more water than a fresh cutting can use. Light, frequent watering keeps oxygen in the plug. Once roots show at the base, the plug lifts out and drops straight into the hole of a Grodan Gro-Block. Its round profile matches that hole, and the firm vertical fibre keeps tight contact with the block. That contact lets roots cross into the block quickly instead of circling the plug. Saturate the block fully first, then water generously for the first few days after the move. Loose plugs pour straight from the case into cell trays, so loading a bench goes quickly.

Key Features

• 1.5 in Round With Slit: The slit closes around a cutting stem for firm, even contact.
• Fits the Gro-Block Hole: Rooted plugs drop straight into a Grodan block with tight contact.
• Vertical Fibre Structure: Each plug keeps its shape when lifted and transplanted.
• Air and Water Balance: Small and large pores hold moisture and oxygen together.
• Uniform Density: Water, nutrients and pH spread evenly from plug to plug.
• 2,000 Per Case: Loose plugs load quickly into individual-cell trays for weekly clone runs.

Technical Specifications