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how to plant marijuana seeds in rockwool

Finally, the dense sheets enter a large oven. The heat activates the binding solution and enables the wool fibres to hold their shape.

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.

Can Rockwool Be Composted?

If you’re growing in soil, you can transplant the Rockwool cubes directly into your new growing medium. Soil growers have a variety of choices when it comes to what to do next. You can transplant into plastic or fabric pots, place your plants into greenhouses or polytunnels, or plant them directly into garden beds.

3. Put your clones into cubes: Use a skewer to create a sizeable hole in the top of each Rockwool cube. Inset the stem of your cutting into the hole, gently pushing it so it reaches the bottom half of the block.

Give your plant one last prune before it enters the flowering stage. This will allow light to penetrate the canopy so each bud site can thrive.

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.

Items you will need:

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.

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

Do not add any nutrients to your Rockwool Cubes. The one on the left got nutrients, the other two did not.

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.

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.

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.