Description
Seed, root and transplant in one block of clean, buffered coco
The Jiffy Growblock is a propagation block made from 100% RHP-certified coco coir, held together by a fine biodegradable PLA netting. It arrives as a flat, dry compressed plate that swells into a firm 50 mm or 100 mm square block when soaked, making it growing medium and container in one. The coir is washed, calcium-buffered and given a small starter charge of nutrients, so seedlings and cuttings get a stable, airy start.
Key Benefits
- Air and water in balance – about 30% air-filled porosity with 63% water holding capacity, so young roots stay moist without sitting wet
- Buffered, low-salt coir – extra washing and calcium buffering guard against early calcium deficiency
- Air-pruned, fast-rooting – roots fill the block and branch rather than circling, for strong plants at transplant
- Less transplant shock – the whole block goes into the next pot, slab or system with the roots undisturbed
- Fits any watering method – overhead, ebb and flow or NFT
- Plant-based netting – PLA made from corn starch, compostable to EN13432
Why Do Young Plants Stall After Transplanting?
Most early setbacks start in the root zone: a plug that dries out or stays waterlogged, salts in poorly washed coir, or roots torn when a seedling is pulled from a tray. Unlike inert stonewool, coir buffers water and nutrients and spreads moisture evenly through the block, supporting steady root development and nutrient uptake, and the Growblock is planted out whole so the roots are never disturbed. Jiffy list tomatoes, peppers, cucumbers, melons, salad greens, strawberries and bedding plants among the crops it suits best.
How to Use
- Hydrate: stand the blocks in a tray, ideally with drainage, and soak with lukewarm water until fully swollen
- Plant: sow directly, or set in a rooted Jiffy-7C plug or cutting once roots show – Jiffy pair the two for the best start
- Water: keep evenly moist in good light away from temperature extremes, and avoid overwatering
- Feed: the built-in nutrient charge is small – begin a light feed after 7–10 days
- Transplant: when roots show at the sides, plant the Growblock intact into coco, soil, a slab or a hydroponic system
Technical Specifications
- Brand: Jiffy
- Product: Jiffy Growblock (coco coir)
- Block size: 50 mm × 50 mm, or 100 mm × 100 mm (about 55 mm high when expanded, with a planting hole of about 25 mm)
- Substrate: 100% coco coir, RHP certified, extra-washed and calcium-buffered
- Netting: PLA (corn-starch based), biodegradable, compostable to EN13432
- Supplied: Dry compressed plate that swells on soaking
- pH: 5.7–6.2
- EC: 1.1 mS/cm (±0.3)
- Air-filled porosity: 30%
- Water holding capacity: 63%
- Total pore volume: 93%
- Dry bulk density: 82–88 kg/m³
- Organic content: Over 99%
- Starter nutrients: Yes – begin feeding after 7–10 days
- Irrigation: Overhead, ebb and flow, NFT
Frequently Asked Questions
Is a Jiffy Growblock the same as a rockwool block?
No. It is 100% coir, an organic material that holds and buffers water and nutrients like a sponge, whereas stonewool is inert and lets solution drain through. Coir also re-wets easily if a block dries out.
Can I put a Jiffy-7C or other plug into a Growblock?
Yes. Jiffy say any propagation plug can be transplanted into a Growblock, and recommend Jiffy-7C coir plugs or Preforma for the best start.
Do I need to buffer or rinse the blocks first?
No. The coir is already extra-washed and calcium-buffered, with a small nutrient charge added. Just soak in lukewarm water and plant once the blocks have fully expanded.
Do I remove the netting when transplanting?
Jiffy recommend planting the Growblock intact. The PLA netting is plant-based and biodegradable, so the block can go straight into the next pot, slab or system.
Works Well With
