diowk
Active Member
I used to have a lot of trouble starting seeds in rockwool successfully. I ended up finding my own method after experiencing bad germ rates with all conventional methods. I've tried everything I could possibly think of to see what works best and I've landed on this method. Now I get 100% germination every time with good seeds and theyre always very healthy and happy. Heres what I've learned:
1. DONT USE THE PAPER TOWEL METHOD! This is the dumbest technique that everyone seems to be doing. It DOES NOT help the seed germinate. It only tells you which seeds are viable so you dont have to wait for a bunk seed thats never going to sprout. The other reason for doing this is because the holes in rockwool cubes are too deep for seeds so by having a 1/4"-1/2" taproot before they go into the rockwool, the seeds wont damp off since they are close to the surface and not buried way to deep. The problem is that you need to be very precise, very delicate, and use completely sterile tweezers or something to get them in without risking damaging the vulnerable tap root and risk lowering your success rate. For most people however, this will only result in lower germination rates and its COMPLETELY unnecessary using this method. Just have patience, when 9 pop and 1 doesnt, you know its a bunk seed... and rockwool is cheap. Ask yourself what seems like a better medium: something designed for rooting plants or something designed for wiping counters....
2. Research your breeder's website and on the seed pack for germination instructions. Many breeders will tell you what works best for their seeds and sometimes contain useful information such as the proper EC for germination and whether or not they should be soaked prior to germinating.
3. Pre-soaking your seeds is a technique that should only be used with older seeds (more than 2 years) and when breeders advise it but its totally unnecessary for fresh healthy seeds. Presoaking healthy seeds is riskier than not doing so.
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On to the actual method
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1. Presoak cubes in non-chlorinated water at a ph of 5.5 for an hour. (you dont need to soak them overnight)
2. Remove cubes from the 5.5ph water and give them a quick dunk or watering with water at a ph of 5.8 and veg nutes at a ppm of 200-300 (you can use a little superthrive or something if you want just make sure the directions say its okay for seedlings and use LESS than what they recommend for seedlings. Youll still get benefits from too little but too much will cause major problems. And they will do just fine with plain water so theres no such thing as too little really but the closer you get it to the sweet spot, the faster and stronger your seedlings will grow. Ive had best results with a ppm of 300 or a little less.
3.*this step is key to great germ rates and Ive never seen it mentioned anywhere else*- scrape a fluffy piece of rockwool off the side of your cube and place it in the hole. This will allow you to control the depth at which you plant your seed and is why we dont need to use the paper towel method. Make sure your not packing it in there, you just want it to be able to keep the seed from falling.
4. Pinch the rockwool BEFORE you put the seed in, this gives you more control on the seed depth since you could easily push the seed down by doing this step afterwards. It also makes planting a lot quicker and easier once you start droppin seeds. The proper way to pinch rockwool is by using your forefinger and your thumb to SCRAPE (your not actually pinching it) the rockwool from corner to corner in and X pattern. Just keep scraping until the hole is closed and the rockwool around the hole feels loose and fluffy. Now take something pointy and find that hole again but only open it up enough so you can see where it is when you go to put the seed in. Now the hole has been filled loosely with fluffy rockwool capable of supporting the seed, the rockwool on top is also fluffy and loose, the hole is just large enough to be visible, and planting will actually feel more like planting in soil than in rockwool and your seeds will be much happier too.
5. Place seed in pointy side down the same way you would in soil. About 1.5x the length of the seed. (If its too deep, it wont srpout. If its not deep enough, the taproot will grow above the rockwool and youll have to push it back down which you CAN do no problem, but it stresses it out and will slow it down a bit. This is the only part that takes a little practice. If I had to choose between too deep or too shallow I would choose too shallow every time. Keep that in mind if you dont know what your doing. Now "pinch" or scrape the rockwool back over the seed to close it up again. This will be quick and easy since its been closed once already and it wont move the seed.
6. Place in a propagator (humidity dome) with a thin layer of moistened perlite. Use a heat mat underneath and you MUST USE A THERMOSTAT!!! PLACE THE PROBE INSIDE THE HOLE OF AN EXTRA ROCKWOOL CUBE you have soaked with the others but havent scraped or planted in obviously. Set thermostat to 69 degrees. Mist everything. Keep in total darkness untill they srpout. This is important. Do dont put them directly under a light. Keep vents of propagator closed until the first sprout then slowly open them every day to get them used to a lower humidity gradually and so they dont damp off. Do it too fast and the seedlings will be in lower than optimal humidity which wont really hurt them just slow them down a bit but do it too slow and they will damp off and this is going to cause a sick seedling. They will look droopy and have stunted growth. As soon as you give them air they will perk up in a matter of hours.
If I deviate from this method in any way I will lose seeds but if I do all these things just as I have laid out I get 100% germination every time with good seeds.
Hope this helps!
1. DONT USE THE PAPER TOWEL METHOD! This is the dumbest technique that everyone seems to be doing. It DOES NOT help the seed germinate. It only tells you which seeds are viable so you dont have to wait for a bunk seed thats never going to sprout. The other reason for doing this is because the holes in rockwool cubes are too deep for seeds so by having a 1/4"-1/2" taproot before they go into the rockwool, the seeds wont damp off since they are close to the surface and not buried way to deep. The problem is that you need to be very precise, very delicate, and use completely sterile tweezers or something to get them in without risking damaging the vulnerable tap root and risk lowering your success rate. For most people however, this will only result in lower germination rates and its COMPLETELY unnecessary using this method. Just have patience, when 9 pop and 1 doesnt, you know its a bunk seed... and rockwool is cheap. Ask yourself what seems like a better medium: something designed for rooting plants or something designed for wiping counters....
2. Research your breeder's website and on the seed pack for germination instructions. Many breeders will tell you what works best for their seeds and sometimes contain useful information such as the proper EC for germination and whether or not they should be soaked prior to germinating.
3. Pre-soaking your seeds is a technique that should only be used with older seeds (more than 2 years) and when breeders advise it but its totally unnecessary for fresh healthy seeds. Presoaking healthy seeds is riskier than not doing so.
---------------------------
On to the actual method
---------------------------
1. Presoak cubes in non-chlorinated water at a ph of 5.5 for an hour. (you dont need to soak them overnight)
2. Remove cubes from the 5.5ph water and give them a quick dunk or watering with water at a ph of 5.8 and veg nutes at a ppm of 200-300 (you can use a little superthrive or something if you want just make sure the directions say its okay for seedlings and use LESS than what they recommend for seedlings. Youll still get benefits from too little but too much will cause major problems. And they will do just fine with plain water so theres no such thing as too little really but the closer you get it to the sweet spot, the faster and stronger your seedlings will grow. Ive had best results with a ppm of 300 or a little less.
3.*this step is key to great germ rates and Ive never seen it mentioned anywhere else*- scrape a fluffy piece of rockwool off the side of your cube and place it in the hole. This will allow you to control the depth at which you plant your seed and is why we dont need to use the paper towel method. Make sure your not packing it in there, you just want it to be able to keep the seed from falling.
4. Pinch the rockwool BEFORE you put the seed in, this gives you more control on the seed depth since you could easily push the seed down by doing this step afterwards. It also makes planting a lot quicker and easier once you start droppin seeds. The proper way to pinch rockwool is by using your forefinger and your thumb to SCRAPE (your not actually pinching it) the rockwool from corner to corner in and X pattern. Just keep scraping until the hole is closed and the rockwool around the hole feels loose and fluffy. Now take something pointy and find that hole again but only open it up enough so you can see where it is when you go to put the seed in. Now the hole has been filled loosely with fluffy rockwool capable of supporting the seed, the rockwool on top is also fluffy and loose, the hole is just large enough to be visible, and planting will actually feel more like planting in soil than in rockwool and your seeds will be much happier too.
5. Place seed in pointy side down the same way you would in soil. About 1.5x the length of the seed. (If its too deep, it wont srpout. If its not deep enough, the taproot will grow above the rockwool and youll have to push it back down which you CAN do no problem, but it stresses it out and will slow it down a bit. This is the only part that takes a little practice. If I had to choose between too deep or too shallow I would choose too shallow every time. Keep that in mind if you dont know what your doing. Now "pinch" or scrape the rockwool back over the seed to close it up again. This will be quick and easy since its been closed once already and it wont move the seed.
6. Place in a propagator (humidity dome) with a thin layer of moistened perlite. Use a heat mat underneath and you MUST USE A THERMOSTAT!!! PLACE THE PROBE INSIDE THE HOLE OF AN EXTRA ROCKWOOL CUBE you have soaked with the others but havent scraped or planted in obviously. Set thermostat to 69 degrees. Mist everything. Keep in total darkness untill they srpout. This is important. Do dont put them directly under a light. Keep vents of propagator closed until the first sprout then slowly open them every day to get them used to a lower humidity gradually and so they dont damp off. Do it too fast and the seedlings will be in lower than optimal humidity which wont really hurt them just slow them down a bit but do it too slow and they will damp off and this is going to cause a sick seedling. They will look droopy and have stunted growth. As soon as you give them air they will perk up in a matter of hours.
If I deviate from this method in any way I will lose seeds but if I do all these things just as I have laid out I get 100% germination every time with good seeds.
Hope this helps!
This is actually the purpose of this technique; to plant the seed in the medium its going to be growing in. Its a lot easier in soil than it is in rockwool cubes with holes that were sized for cuttings though. Thats why I made this post.
