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germinating cannabis seeds in rockwool

seedlings in them you would not have to water for about a week maybe longer.

germinate them them move them to the rock wool cubes


you dont use a humidity dome for starting seeds and second rockwool cubes will not dry out. they retain allot of water, and with

I use the paper towel method 100 percent success rate for me, then once the little white tail pops out of the seed, then move the seeds to the 1 inch rock wool with the tail facing down in the hole then lightly put a little piece of rock wool over the hole that the seed is in.

another ethod that ive HEARD works is just to put in a shotglass over night, see what happens ins the seed absorbs the moisture until it pops. thats what ya want..

On top of that, Rockwool is like asbestos, you don’t want to be squeezing it or breathing it or generally touching it any more than you need to. Here is a good article on some of the health concerns of Rockwool. I use it because it is what works best, but be cognizant to the fact that it is a potentially dangerous substance to be making contact with so don’t do anything more than you need to with it.

Get a bowl or some other container that is big enough to fill with water and have room left for your Rockwool cubes. Your average salad bowl will work fine for 3 Rockwool cubes, if you are planning on doing more than you will need a larger container.

Important: Do not let the PH of the water go below 5. A Ph this low will damage the fibers of the Rockwool Cube

Using either a PH test kit or a Ph meter, determine the Ph of the water. Water comes out pretty alkaline, usually around 7.4, so you will need to acidify it a little bit to bring that Ph down to the desired level. Aim for as close to a Ph of 5.5-6 as you can get.

To accomplish this, use either Ph down chemicals, or lime juice (as it’s acidic). Add these to the water in small increments (VERY SMALL), and test the water to see where the Ph is. Continue doing this until you have a Ph of 5.5-6.

They should look like this:

We don’t recommend using the same Rockwool cube to start a new seed. Although the material itself prevents microbial growth, small pieces of roots and organic matter can end up trapped between the fibres, which can encourage the growth of detrimental fungi.

The inception of mineral wool came about when observers at a volcano watched strong winds whip lava into woolly fibres.

Is Rockwool Reusable?

Rockwool also poses a potential health hazard to growers. New Rockwool cubes can contain a lot of loose fibres and dust. These particles can end up in the air, and even on your skin and in your eyes, mouth, and lungs. Much like asbestos, tiny fibres can build up in the lungs over time if you work with new Rockwool cubes every day.

For this key step you’ll need:

Once your seedling looks ready for a new home, you’ll find it incredibly easy to move it directly into a pot full of soil or a hydroponic net pot. Unlike transplanting from soil, you don’t need to break apart the initial growing medium or deal with any mess. Simply pick up the cube and slot it into its destination.