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how to germinate cannabis seeds in rockwool

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.

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.

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

Here is what it should look like:

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.

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.

Pre-sprout your seeds in a moist paper towel and then plant in the rock wool once the spouts are over 1/2" I did this and got 14/20 sprouted from which I had to pick 7 and they are all doing AMAZING.

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

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.

Dwezelitsame

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

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

germinate in paper towl folded up, leave a littel pocket, and moisten the paper towe, and keep moist. leave it in a tupperware contaier in the dark for 3-7 days, keeping the towel moist, and you should see the embryo.

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..

This method is as old-school as it gets, drop your seeds in some dirt, add water, and you’re done.

Step 2: Now, you need to plant your seeds at the right depth. A good rule of thumb is to plant seeds 2 times deeper than the width of the seed.

Step 1: Purchase quality soil from a reputable source. You want soil with good drainage, this allows for air exchange; seeds need moisture but you don’t want to drown them.

How To Germinate With Plugs:

If you have any questions, suggestions, or comments, please leave them below and I will do my best to answer all of them.

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Peat plugs hold more water than air compared to rockwool cubes, so they aren’t ideal for hydroponic grows.

This method is not so much a way to fully germinate your seeds, but rather ensures rapid and reliable germination.