Grodan Delta is the basis for an easy to steer the propagation process, which results in uniform, good quality plants. Each block guarantees uniform water and nutrient distribution.

Grodan Delta scores high in saturation and firmness, which means it always performs well in highly mechanized propagation processes.

Delta Technology ensures uniform distribution of water and nutrients throughout the block. Newly transplanted plants benefit thanks to the good availability of water and nutrients, which encourages he roots to penetrate deeply into the substrate slab.

What is Rockwool?

Grodan Stonewool (rockwool) is made from molten rock spun into cotton candy-like fibers and then compressed into cubes, blocks, or slabs. Where other rockwool brand manufacturers cut all sizes from one batch of wool, Grodan is unique by making different types of fibers. The purpose is to support the requirement of the plant in the different plant stages. Grodan has a tremendous capacity for absorbing nutrient solution while retaining plenty of oxygen for rapid plant growth. Grodan comes in graduated sizes. Seedlings started in cubes are easily transferred to blocks and then onto slabs, if desired. Seedlings or cuttings started in the Grodan cubes can also be transplanted into more traditional planters and growing mediums.

Usage Instructions

Soaking

• Saturate the Grodan Gro-Blocks with pH 5.5-6.5 water when starting cuttings
• When transplanting, use the same strength nutrient solution to soak the new media as you were feeding the plant.
• If submerging the blocks to saturate, keep them submerged in the solution until bubbling stops

Irrigation

• If using a drip irrigation system, use one drip stake per Grodan Gro-Block. Irrigate as needed to keep the block moist but not saturated.
• If using an ebb and flow system, irrigate when the Grodan Gro-Block is approximately half its fully saturated weight.
• If hand watering, keep the block moist but not full saturated.
• Do not over saturate the block after the initial soak as this can slow plant growth

Transplanting

• Place a rooted cutting, grown in Grodan starter, into the hole of the Grodan Gro-Block
• Do not water for several days until the plant has rooted into the Grodan Gro-Block but do not allow the block to go completely dry
• If needed, lightly mist once per day to keep the top of the block moist
• Do not allow the block to sit in standing water

Transplanting for Larger Plants

• For smaller short term crops, Grodan Gro-Blocks are all you need. To grow larger plants, you can transplant Gro-Blocks on to Grodan Slabs , Grodan loose media, or soil
• Prior to transplanting, make sure that the plant is well established with multiple roots appearing on the bottom of the Grodan Gro-Block
• When transplanting to a container or outdoor garden, make sure the new media is very wet at the time of initial transplant