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how to germinate cannabis seeds in rockwool

once split i transfer to cup with holes in bottom covered with a baggie and rubber band for a little greenhouse effect once soil break i remove plastic once again all heating pad .. i normally use heating pad until first transplant at 3 or 4 weeks old

i would have soaked mine over night first 75 percent of time is split the next day

i have a Hydro set up also so i have been starting seedlings in rockwool for years.

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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.

from there go to paper towel all in dark on heating pad at about 80 degrees

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

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

Now that we have the Ph adjusted water, it’s time to stabilize and hydrate the Rockwool cubes in it. Insert the Rockwool Cubes into your container and let them soak for roughly 1 hour. Once the hour is up, the cubes will be big and fat with water. Take them out of the bowl of water and put them somewhere you don’t mind getting a little wet. Save the remaining water for step 3.

About 2-3 weeks after germinating, you are ready to transplant these babies into the hydroponic system of your choice. A good rule of thumb to go by is that you want to transplant them once the first roots begin poking out of the Rockwool cube. Don’t wait too long though, as eventually the roots will begin tangling around the cube since it is their only source of water. You want to catch them right as they pop out, so that when you transfer them into your hydro system the roots will grow down into the system, and not just try to feed off the Rockwool cube alone.

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

Fill the container/bowl with water from your tap. You may also choose to use water filtered through a britta or reverse osmosis (R/O) water, I’ve had success with all 3 of them so whichever you have on hand will work fine.

Depending on how hot it is (and other factors) you may need to water your cubes 1-4 times a day. Use the Ph adjusted water when doing so (that’s why I had you save the leftovers from step 2). If you already threw that water out, go make another batch of Ph adjusted water and keep it in a separate bottle or container for watering. Note: Do not over water, in fact while some say to water 1-4 times a day, I did it only once a day when I got home after work.

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.

The added benefit of using beneficial microbes products is they protect cannabis roots and root zones, and speed up root development.

As a hydroponics marijuana grower, you need total control over how your plants absorb water, oxygen, and hydroponics nutrients. Fact is, what you choose as the environment for your cannabis…

Don’t Drown Your Cannabis Seeds

That’s why I germinate marijuana seeds in the media they’ll grow in.

If they’ve been moist that long and haven’t germinated, they’re most likely not going to.

Note that rockwool must be pre-treated before use to get its pH where you want it.