Posted on

how to germinate cannabis seeds in rockwool cubes

As you can see, Rockwool cubes offer growers plenty of benefits, from improved aeration to pathogen prevention. However, more environmentally concerned growers choose to avoid them because of how they’re made, and what they’re made of.

Overwatering kills many grows before they even get started. Damp conditions can foster fungal pathogens that quickly destroy seedlings. Although Rockwool cubes are largely safe from microbes, excess water can still suffocate roots and hamper growth. Good aeration stops this from happening.

Rockwool is a branded form of mineral wool, a material used primarily as thermal and acoustic insulation in the construction of homes, hospitals, recording studios, and even stadiums.

3. Give Them Room

1. Fill up a shallow bowl with water and test the pH. Add your pH-down product until your meter shows an acidic reading of 5.5.

Rockwool cubes become saturated with water when you soak them, but it quickly drains away. Each cube contains many small spaces between the fibres that help to effectively drain water. Overwatering kills many grows before they even get started. Damp conditions can foster fungal pathogens that quickly destroy seedlings. Although Rockwool cubes are largely safe from microbes, excess water can still suffocate roots and hamper growth. Good aeration stops this from happening.

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

Yes! Rockwool contains basalt, which works great as a soil amendment in general. Once it becomes weathered over time, it releases nutrients such as phosphorus into the soil.

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.

Rockwool Cubes are designed to maintain the correct water to air ratio and squeezing them may damage their structure. Some of the marijuana forums advocate doing everything from squeezing them completely dry, all the way to flinging them around like paintbrushes in order to get excess water out. None of that is necessary, leave it as it is. It will stay moist for several days without needing to be watered this way as well.

Items you will need:

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

Take 1-2 seeds and insert them carefully into the holes. Use a toothpick or similar object to push them down to the bottom, as you want them to be at the bottom of that hole. Rip or push a piece of the Rockwool over the hole (you don’t have to fill it completely), so that the seed can germinate in a dark moist environment.

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.

Rockwool Cubes have a PH of roughly 7.8. This is pretty alkaline, yet our plants prefer to grow in a slightly more acidic environment (between 5.5 – 6.5). In order to prepare our Rockwell cubes for the seeds, we need to soak them in some PH adjusted water, that way they have everything the seeds need to germinate and sprout; water and a slightly acidic environment.

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.

germinate them them move them to the rock wool cubes

Strains,
Whitewidow x Euforia x "Mindfuck".
Ghost of Ghana 100% equatorial sativa. (special).
Food of Gods secret strain from village of south Africa! (special).

Well-Known Member

the paper towel method ALWAYS works. IMO

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

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