Hortiwool is an Inert growing medium made from special mineral fiber material produced from slags, limestone and natural rocks to prepare an inert growing medium for use as a soiless medium, as part of a soiless medium mixed with peat moss, perlite, and vermiculite, or as a soil amendment to enhance soil conditions.

Hortiwool provides plant growth equal to or better than peat-lite or sawdust media. Due to it's inert nature, Hortiwool remains stable and does not adversely affect the pH of nutrient solutions. This material can be re- used and sterilized while remaining light weight in nature. No phenolic resins are added, and based upon percolation tests run by Aquatrois Corp. of America, no wetting agents are required. Hortiwool's superior water retention characteristics also provide a high pores-to-fiber ratio.

Hortiwool provides a medium that reduces fungus growth by providing a dry stem environment at the plant base. Replanting or transfer planting is easily accomplished using Hortiwool.

GRODAN PROPAGATION CUBES:

• Inert growing medium
• Makes transplant much easier
• Chemically stable
• Contains Copper and Iron minerals that reacts with nutrient solution
• Makes nutrient uptake very easy
• Lasts indefinitely with care and sterilization
• Suited for seedlings and cuttings

PROPAGATION BLOCKS:

They are used for transferring seedlings started in the propagation cubes, when it is desired to hold them prior to putting them onto the slabs.

• Ideal for growing vegetables and herbs
• Easy water intake
• Used for transferring seedlings started in Propagation cubes

Stonewool is not alkaline!

It is a common belief that Grodan is alkaline and that one has to continuously adjust the pH. This is not true. When Grodan is new it contains some residual lime from production. Everybody should soaks the rockwool in no lower than pH 5 water the day before use. This is done to dissolve the lime. The lime will make the pH value raise a full point. Immediately before use; you flush the rockwool with your nutrient solution. When you flush, you also flush out the dissolved lime. From this point onwards rockwool does not change the pH in anyway.

Exception: If you condition your rockwool with a pH lower that 5, you may also damage the fiber itself. As an example: If you use pH 4 water for conditioning, the pH the day after will be 7. The lower pH you use the higher it jumps. Once the fibers are damaged it might take quite a while before the pH stabilizes. So never go below pH 5 with rockwool.

Why does pH change?

When the plant grows the pH goes up because of the root activity. If the pH is not going up, your plant is not growing! When the plant gets ready to set flowers or fruit, the pH will briefly drop. So when you notice this drop, it is time to change to your bloom-solution. When your propagated plant have grown into the bigger DM blocks, you will often go into a period of rapid growth. This means that your pH will go up high. Your EC (conductivity) will also tend to go up.

Be sure to water the blocks enough. You need to check EC and pH in the blocks everyday. During this initial growing on, water the blocks every 6-7 hours, but only while the light (1000W) is on. If the pH or the EC in the block is too high, the quickest way to change it is to top water with balanced nutrient solution. As the plants get bigger 3-4 weeks after potting up the A0 cube, you will need to water approx. every 5 hours. (1000 W light)

Set your first watering to start when your light switches on. Be sure to complete the last watering no less than 2 hours before you switch your light off so the blocks are not too wet during the night.

DON’T FORGET to keep a journal.

If you write down what you are doing and what the environment readings are, it is easier for the shop to answer your questions, when you run into a problem.

What are Grodan and stonewool (rockwool)?

First off, Grodan has trademark on the word 'stonewool', as rockwool is now so generic. Rockwool for hoticultural use was invented in Denmark by Grodan in 1969. The product is today used extensively world wide. In North America the majority of greenhouse vegetables are grown in Grodan. Stonewool products are made from basalt rocks and chalk, which come from the Earth. Mimicking Mother Nature’s production of "angel hair" during volcanic activity, the Grodan stonewool manufacturer heats rocks to 1600°C, to create lava. The lava is blown into a spinning chamber, which makes fibers similar to cotton candy.

The fibers are packed into mats, from which Grodan cubes, blocks and slabs are cut. Small tufts of fibers are also produced and bagged as "rockwool granulate". The products make excellent use of natural resources: one cubic yard of rock becomes 37 cubic feet of wool!