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how to start marijuana seeds in rockwool cubes

Sometimes seeds struggle to become established when sown in compact and hard soils. However, they establish themselves quickly and easily within Rockwool cubes. The young roots easily pass through the gaps between the fibres.

Try and refrain from overwatering your Rockwool cubes during the seedling stage. They drain quite fast, and many growers get the impression that they’re underwatering. However, the inside of the cube remains nice and moist and will keep your seedlings happy without suffocating them.

Stabilise the pH and Feed Your Blocks

For this key step you’ll need:

This nutrient supports the growth of every plant cell, aids in energy transfer and photosynthesis, and plays an especially important role during the flowering phase. As a bonus, basalt rock dust also helps to absorb large quantities of carbon dioxide from the atmosphere.

Shred your used Rockwool cubes into fine strips before adding them to your compost pile to speed up the rate at which they release minerals into the soil.

Seeds need air and water to germinate, if there’s too much of one, the other falls short, preventing germination.

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.

So what is the best way to germinate weed seeds? Read on to find out…

3. Soaking Seeds in Water

The paper towel method is similar to soaking seeds in water, but this method will germinate your seeds to the point where the taproot has emerged.

Now, if you can, place them in a tray with a dome on it. This will help create a little humidity in there which seedlings like. This is not mandatory, but it helps. Whichever you choose, take your cubes and put them in a cool dark place, and leave them alone. The temperature should be roughly 68 degrees F, though my house stays at about 72 and they do fine there. I usually place them above my refrigerator and just leave them for a day or two. My lettuce seedlings sprouted with a quickness the last time I tried, and by the 3rdday they had grown so tall that I had to take the plastic dome off of my container because they were bumping up against the ceiling.

Check out this method in action:

This will essentially starve and kill your seedling.

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

germinate them them move them to the rock wool cubes

I don’t know where the paper towel method started, I only know that it has been around far too long. I first learned of it over 30 years ago. It’s hogwash. does it work? Most of the time, but why risk handling a delicate seed and it’s new born tap root when you can simply place the seed in any moist medium and have it germinate? If the seed germinates in a paper towel, which surely can’t sustain the seed, won’t it surely germinate in moist rockwool?

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

germinate them them move them to the rock wool cubes

Also, rock wool is naturally alkaline, so you’ll need to soak it in PH balanced water over night first before putting ANYTHING in it. My plants are currently in rock wool and doing great

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..