Propagation Media

The right propagation media provides the perfect balance of moisture, aeration and physical support that rooting cuttings and germinating seeds need to establish quickly and transition smoothly into their final growing medium. Whether you prefer the proven performance of rockwool, the organic buffering of Root Riot, the convenience of Jiffy pellets or the versatility of small coco blocks, we stock the key propagation substrates trusted by UK growers at every level.
Rockwool Cubes and Slabs
Rockwool (mineral wool) is the most widely used propagation medium in professional horticulture. Made from spun basaltic rock, rockwool cubes offer outstanding moisture retention alongside significant air space — creating the wet-but-airy environment that root initiation demands. Small 25mm or 36mm rockwool cubes are ideal for cuttings and seeds, transplanting directly into larger 100mm cubes or rockwool slabs as root development progresses.
Pre-soak rockwool cubes in pH 5.5 water for 30–60 minutes before use. Rockwool is naturally alkaline (pH 7.5–8.0) and requires pH adjustment before use. After soaking, drain excess water — rockwool should be moist but not waterlogged, with water not dripping freely from the base. Maintain 70–80% RH over rockwool cubes during rooting for best results.
Root Riot, Jiffy and Coco Plugs
Root Riot plugs are an organic-based alternative made from composted tree bark — naturally buffered to pH 5.5–6.5 and teeming with naturally occurring microorganisms. They are ready to use straight from the packet and are particularly popular with growers who prefer organic inputs throughout their growing process. Jiffy pellets expand when soaked in water to form a compact peat-based propagation module. Both types transplant smoothly into soil, coco or hydroponic substrates without disturbing the developing root system.
We have been supplying propagation media to UK growers since 2017. Browse the full range below.