seed in rockwool

BigJon626

Well-Known Member
ok i know to soak the rockwool at a ph of 5.5 but i dont plan on soaking them overnight. after i plant the seed in them do they do under light right away?
 

taipanspunk

Active Member
Not until the seedling breaks out the top of the rockwool.
...correct me if I'm wrong, after the seeds crack and your put them into the rockwool (or starter block, or stg, or whatever starting medium) they need to be placed under light (humid and higher temp). The light then is an environmental trigger for germination to start the sprouting process...
 

BigJon626

Well-Known Member
see this is what im talking about lol ive heard what bolth of you guys are saying. i always thought that the plant broke through the top of the soil because it was heading twords the light(but thats just my opinion with no sci ev lol). but ya its my first time using rock wool with seeds so i dont know
 

Pew

Active Member
Can confirm it does not need light until it breaks the surface. Last few beans, once they got taproot, they went in rockwool, and did not get light until they came through the surface. Used a dome and heating pad inside a cabinet.
 

taipanspunk

Active Member
Can confirm it does not need light until it breaks the surface. Last few beans, once they got taproot, they went in rockwool, and did not get light until they came through the surface. Used a dome and heating pad inside a cabinet.
That's odd... because I always stick it under the light in a dome and wait for the stem to break to the surface... ...I got to try it the other way...
 

Pew

Active Member
Wouldnt be surprised if it works either way.. In the past with dirt, once I got taproot, Id just plant the bare seed in the dirt and stick it under the light, which also worked.
 

BigJon626

Well-Known Member
ok i planted them in rockwool and put them in a little greenhouse with dome in the dark. how long normally till they sprout? and do i only mist not water?
 

Pew

Active Member
ok i planted them in rockwool and put them in a little greenhouse with dome in the dark. how long normally till they sprout? and do i only mist not water?
The rockwool should stay damp. How fast it will dry out depends on your environment, the dome should slow (or prevent) them drying. You *may* not need to provide any water before seeing a sprout break the surface.
 

rjl

Member
4 white widow seeds from Nirvana.
#1. germed in paper towel / distilled water. After 2 days all seeds cracked and root showing.
#2. placed seeds in saturated rockwool cubes placed in hume dome w/lights on 24/0.
#3. After 4 days no further growth.
#4. removed seeds from rockwool & placed in soil with superthrive and 20-20-20 nutes, mixed to manufacturers specification or less.
#5. next day one seed showed growth above soil approx 3/4 of an inch.
Trial and error is an ongoing thing in botany
 

BigJon626

Well-Known Member
i phd my water to 5.5 with lemon and i also did squeeze a little water out of the cubes after so they werent driping wet i dont know if that was bad or not. and my current conditions are dark 74F 47% humidity its almost been one day so ill give it more time.
 

Pew

Active Member
4 white widow seeds from Nirvana.
#1. germed in paper towel / distilled water. After 2 days all seeds cracked and root showing.
#2. placed seeds in saturated rockwool cubes placed in hume dome w/lights on 24/0.
#3. After 4 days no further growth.
#4. removed seeds from rockwool & placed in soil with superthrive and 20-20-20 nutes, mixed to manufacturers specification or less.
#5. next day one seed showed growth above soil approx 3/4 of an inch.
Trial and error is an ongoing thing in botany
Do you know the PPM of the distilled water? I found using R/O water was too bare of micro-nutes (dead). U may have better luck with that distilled water in RW with a little added Calmag+
 

rjl

Member
Checked again today, and the remaining three are still unchanged. They may be stressed or late sprouters. the one that did sprout is showing it's first true node leaves. I placed it in my Hume Dome for comfort and company at a constant 72 degrees.
 

Pew

Active Member
Technical, From 'growers bible'

"Germination:
During germination moisture, heat, and air activate hormones (cytokinins, gibberellins, and auxins) within the durable outer coating of the seed. Cytokinins signal more cells to form and gibberellins to increase cell size. The embryo expands, nourished by a supply of stored food within the seed. Soon, the seed's coating splits, a rootlet grows downward, and a sprout with seed leaves pushes upwards in search of light.

Cannabis seeds need only water, heat, and air to germinate. They do not need extra hormones to germinate. Seeds sprout without light in a wide range of temperatures. Properly nurtured seeds germinate in two to seven days, in temperatures from 70-90'F (21-32·C). Household water contains enough dissolved solids (food) to nourish seeds through their first few weeks of life. Although seeds need only 30-50 ppm of nitrates before they germinate, any more will disrupt internal chemistry. Some growers prefer to use distilled water that contains virtually no dissolved solids to germinate seeds. In fact, a high concentration of dissolved solids (salts) in the water will actually pull moisture out of the seed!

Some seeds have a very hard outer shell, testa, and must be scarified to allow water to penetrate. To scarify, line a matchbox with a piece of fine-grain sandpaper or emery board. Put the seeds in the matchbox and shake for about 30 seconds. Remove the seeds, and make sure they have been scuffed a bit. Just a little scuffing will allow water to enter and set germination in motion."
 

genuineapbts

Active Member
ok i know to soak the rockwool at a ph of 5.5 but i dont plan on soaking them overnight. after i plant the seed in them do they do under light right away?
Everyone has a different opinion on this as you can see. lol This was something I asked too and everyone gave me different answers. I ended up just putting the seeds in the rockwool, then put the rockwool in the hydroton under a 1000 watt mh. Everyone freaked out when I told them that but thats what I did. They all up out of the rockwool within 1-7 days. I just hand watered them for a while and then turned my res on. As for squeezing the rockwool Ive heard you shouldnt do that. You are supposed to kinda shake them off by like flicking your wrist.

I have found you just have to take everyones advice and try what you want even if it is different then what most people suggest. Keep a log or journal so you know what worked and what didnt. Im on my first grow and have learned a ton in the last 4 weeks. lol Good luck!
 
Seeds dont need light until they sprout and even then they dont need a lot of light. But the seeds DO like humidity and a little warmth. I have a rockwool holder with a clear plastic lid and i put it on top of the toaster over for like 5 or 10 minutes until it gets humid and the plastic lid has water vapor on it. And I dont water the rockwool at all. I let the sprouts grow then transfer it to my hydroponic setup.
 
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