Description
The Grodan Vital 1.3m rockwool slab is the longer of the two Vital slabs. 130 x 15 x 7.5cm, taking four to five blocks along its length, so you get another plant per slab and one less slab to plumb across a long bench run.
Vital is built on Grodan's Next Generation wool. It saturates faster and more evenly than older slabs, and water content and EC distribute uniformly through the slab and between slabs. On a slab this length that even distribution matters more, because a gradient from one end to the other is exactly what you do not want when four or five plants are sharing it.
Specification
| Slab dimensions | 130 x 15 x 7.5cm |
| Blocks per slab | Four to five, depending on spacing |
| Wool | Grodan Next Generation, inert and pH neutral |
| Cover | Light-blocking wrap |
| Pre-soak pH | 5.5 to 5.8 before use |
What it suits
Vital is used commercially on the major greenhouse crops. Tomatoes benefit from the uniform water distribution and the clean EC replacement. Sweet peppers show fast growth, uniform stem development and early setting. Cucumbers and aubergines run well on it too. Indoors it does the same job under a row of blocks, and the 1.3m length is the one that suits a full-width bench.
Before you use it
Rockwool leaves the factory with a naturally high pH, so it has to be conditioned before anything goes on it. Soak for 24 hours in a weak nutrient solution under 1.0 EC, adjusted to pH 5.5, then let it drain. Cut the drain slits in the cover only once the slab is in position and fully saturated, and stand your blocks on it after that, not before. On a 1.3m slab, check it has wetted right through at both ends before you commit plants to it.
Which rockwool size do I need?
Rockwool works as a ladder. You start small and pot on into the next size up, each time without disturbing the roots. Here is the full range we stock and where each one sits.
| Product | Size | Where it fits | Takes |
|---|---|---|---|
| Grodan Propagation Cubes | 25mm or 36mm | Seed and cutting | Bare cutting or seed |
| Cultiwool Loose Mini Cubes | 10mm, 90L or 200L | Loose fill, any pot | Fills pots and trays |
| Cultiwool Mapito | 80L bag | Loose fill, any pot | Fills pots and trays |
| Grodan Block 3" | 7.5cm | First pot-on | 2.5cm or 3.6cm hole |
| Grodan Improved GR4 3" | 3 x 3 x 2.5" | First pot-on | Pre-formed hole |
| Grodan Block 4" | 10cm | Veg | 2.5cm or 3.6cm hole |
| Grodan Improved GR10 4" | 4 x 4 x 3.1" | Veg | Pre-formed hole |
| Grodan 6" Hugo Block | 150 x 150 x 140mm | Veg to harvest | 36mm hole |
| Grodan 6" Hugo, dripper hole | 150 x 150 x 140mm | Veg to harvest | 36mm hole plus dripper hole |
| Grodan Improved Hugo 6" | 6 x 6 x 5.8" | Veg to harvest | Pre-formed hole |
| Cultiwool 8" Big Daddy Block | 20 x 20 x 19.5cm | Full cycle, large plants | Takes an 8" cap |
| Cultiwool 25cm X-Fibre Mini Slab | 25.2 x 19.5 x 7.5cm | Under a block, full cycle | One 6" or 8" block sits on top |
| Grodan Vital Slab 1m | 100 x 15 x 7.5cm | Multi-plant, full cycle | Three to four blocks |
| Grodan Vital Slab 1.3m (this product) | 130 x 15 x 7.5cm | Multi-plant, full cycle | Four to five blocks |
Sizes are nominal. Blocks are sold as singles or in strips depending on the line.
Goes well with
- Grodan 6" Hugo Block – Four or five of these stand on a 1.3m slab. The standard pairing.
- Grodan Vital Slab 1m – The shorter version, when your bench run will not take 1.3m.
- Cultiwool 25cm X-Fibre Mini Slab – The alternative approach: one slab per plant, so each one gets its own water content and EC.
- Octa-Mitter 360 Dripper on Stake – One per block along the slab, adjustable 0 to 60 L/h.
Frequently asked questions
1.3m or 1m?
Measure your bench or tray run first. A 1.3m slab takes four to five blocks, the 1m takes three to four. On a long run the 1.3m gives you fewer joins and fewer feed lines to set up.
Slab or one block per plant?
A slab is cheaper per plant and simpler to plumb, but every plant on it shares one reservoir, so they steer together. A mini slab per plant costs more and gives you individual control. Neither is wrong, it depends how uniform your plants are.
Do I have to soak it first?
Yes. 24 hours in solution under 1.0 EC at pH 5.5. Check both ends have wetted through before you cut the drain slits and stand blocks on it.
How do I irrigate a slab?
One dripper per block, little and often, aiming for 10 to 30 percent run-off from the slab. See Dripper Systems, Run to Waste Systems and pH & EC Meters.
Browse more
Rockwool · Growing Media · Dripper Systems · Run to Waste Systems · Grow Room Irrigation
