GRODAN SBS 36 TRAY OF 77

Description

Grodan SBS 36 Tray of 77 is a professional rockwool propagation tray from Grodan — the world’s leading manufacturer of horticultural stone wool — containing 77 individual 36mm propagation plugs arranged in a standard tray format for high-density seedling and cutting propagation. We have been recommending Grodan propagation products to UK growers since 2017 as the benchmark quality standard for rockwool-based propagation in both commercial and hobby cultivation environments.

Professional High-Density Propagation from Grodan

Grodan’s SBS (Starter Block System) 36mm plugs are specifically engineered for the rooting phase — smaller than standard 40mm or 75mm cubes, the 36mm format provides an appropriate root zone volume for young cuttings and seedlings while remaining compact enough to fit 77 units into a standard propagation tray. This high plant density maximises the productive use of propagation lighting and tray space, allowing you to start large batches of cuttings simultaneously for efficient, uniform clone production.

Grodan stone wool is manufactured to precise, consistent specifications in terms of fibre density, water retention and drainage characteristics. Every batch of Grodan SBS plugs performs identically, allowing you to calibrate your propagation protocol — irrigation frequency, humidity, lighting and temperature — with confidence that the growing medium is not introducing variability from batch to batch. This consistency is what distinguishes Grodan from less precisely manufactured rockwool alternatives.

Preparation and Use

Soak plugs in pH 5.5–5.8 adjusted water for 30 minutes before use, then allow to drain without squeezing. Make cuttings, dip in Root!T rooting gel, and insert into the pre-cut hole in each plug. Cover with a humidity dome and maintain 22–26°C and 75–85% RH until roots emerge at the plug base. Transplant directly into larger rockwool slabs, coco or hydroponic systems without removing the plug.

Pairs with Root!T rooting gel, a Garland propagation tray and lid, SunBlaster LED propagation light, and a heat mat for a complete professional propagation setup.