Rockwool seedlings not looking great :/

NeonTetra

NeonTetra

Member
Hey all! New grower here having some difficulty. Going to just drop the specs and photos and hopefully someone can help.

Medium: Rockwool (24 hour presoak @ 5.5 pH)
Water: Homemade RO (000ppm)
Light: 4x 100 watt equivalent daylight CFL at 1 foot distance. 20/4.
Temps: 70-80 deg at plant level
Humidity: 70-80%
Fan: 24 hr oscillating
Nutes: GH Flora Series, manufacturers schedule @ 1/4 conc.
Strain: Chocolope
Age: 16 days from breaking surface
Primary technique: NFT

Procedure:
1.) germed in 1" rockwool, hand water RO @ pH 5.8
2.) transferred to 3" rockwool once multiple roots appear out 1" cube
3.) Water with DIY ebb and flow designed to automate hand watering. Water by weight at 20 - 40 % total weight loss (every 2-3 days), 10 minute flow to 1/3rd height of cube. Air stone running 24/7, grow shop generic pH adjuster.
4.) Began feeding 1/4 conc, (120 ppm, pH 5,8 when roots appeared out bottom of 3" cubes, second true leaves just forming

I extracted and tested water from cubes. pH @ 6.4, 150 ppm.

In addition to what you can see in the pics, the plants have slowed growth considerably, including the roots. There are about a dozen or so roots shooting about 1-2cm out the bottom of the 3" rockwool with slightly browning tips due to some air exposure. I'm eager to transfer to NFT as I expect it will be more stable than this ebb-and-flow, should I do this now or make some attempt to continue root development (after I fix my current issue).

Is this deficiency? Toxicity? pH too high? Or something awfully wrong with this ebb-and-flow seedling nursery I rigged up?

post-803110-14073447971648.jpg
post-803110-14073448802693.jpg
 
ficklejester

ficklejester

Well-Known Member
Increase water to 400ppm or so. Move your lights closer, unless you want them stretching like that. Might drop your ph by .5 or so, plants vary on what they like.
 
NeonTetra

NeonTetra

Member
Dr.Pecker said:
That long stem should be root mass not stalk.
Click to expand...
All of the stem growth took place over the course of about 12 hours and stopped. These are 90% sativa so I was thinking that had something to do with it? I will be transferring to net pots in nft so could certainly bury some stem in hydroton or something.

Any tips on seedling care at this phase? Have had a rough time finding info on what to do between 2nd and 4th set of true leaves.
 
Last edited:
NeonTetra

NeonTetra

Member
ficklejester said:
Increase water to 400ppm or so. Move your lights closer, unless you want them stretching like that. Might drop your ph by .5 or so, plants vary on what they like.
Click to expand...
Lights are 4 100W equiv CFLs and give off a fair amount of heat. Any closer than 12" and temps start to rise to 85 or more at leaf level (hope I can properly call it a "canopy" one of these days...)
 
NeonTetra

NeonTetra

Member
Have seen so many rock wool seed grows online. Recommendations for where I am now? What causes the stem to grow that way vs. going towards roots, assuming that stem popped up about 3" in half a day while under 60 watt equivalent cfls at 3" ( I had to move the lights up that day to keep them from touching directly).
 
Mashkiki'inini

Mashkiki'inini

New Member
NeonTetra said:
Have seen so many rock wool seed grows online. Recommendations for where I am now? What causes the stem to grow that way vs. going towards roots, assuming that stem popped up about 3" in half a day while under 60 watt equivalent cfls at 3" ( I had to move the lights up that day to keep them from touching directly).
Click to expand...
Can someone confirm that if a seed is germinated in rockwool that it has the potential to grow a stem instead of growing roots? I've never heard of this? If this is true, how is it prevented?
 
Dr.Pecker

Dr.Pecker

Well-Known Member
when you grow a seedling like that and it stretches you want to plant it deeper. also the closer the light the less stretch. All that exposed stem under the sprout leaves is potential root mass.
 
Mashkiki'inini

Mashkiki'inini

New Member
Dr.Pecker said:
when you grow a seedling like that and it stretches you want to plant it deeper. also the closer the light the less stretch. All that exposed stem under the sprout leaves is potential root mass.
Click to expand...
If growing in rockwool, does one use the pre-existing hole to place the germinated seed in? The pre-existing hole depth would then determine how far the seed is from the top surface. This may or may not provide the correct depth. What is the correct depth? I've been told 0.25" from the top surface of the cube.
 
Dr.Pecker

Dr.Pecker

Well-Known Member
Mashkiki'inini said:
If growing in rockwool, does one use the pre-existing hole to place the germinated seed in? The pre-existing hole depth would then determine how far the seed is from the top surface. This may or may not provide the correct depth. What is the correct depth? I've been told 0.25" from the top surface of the cube.
Click to expand...
the seed depth is correct. most people grow clones in rockwool though. one thing the op could do is cut the bottom out of a container and place it around the seedling so its on top of the cube and fill in that container with a medium that way it will simulate a deeper planting.
 
Mashkiki'inini

Mashkiki'inini

New Member
Dr.Pecker said:
the seed depth is correct. most people grow clones in rockwool though. one thing the op could do is cut the bottom out of a container and place it around the seedling so its on top of the cube and fill in that container with a medium that way it will simulate a deeper planting.
Click to expand...
If one grows starting from a seed, the seed would be placed in a rapid rooter, instead of a rockwool cube? Once a root system is formed, the Rapid Rooter is moved to the hydroponic system?
 
Dr.Pecker

Dr.Pecker

Well-Known Member
That's one way to do it. Seeds are generally 20% more vigorous growing than a clone but you have to create a large root system. I do this by planting them deeper after they stretch. If it were me I would only run a clone in a hydroponic system This way you can feed them all the same and you know what you're growing because you've grown the seedling/mother. I'm not saying it cant be done and It's good that somebody has tried it. I wish you guys luck.
 
Mashkiki'inini

Mashkiki'inini

New Member
Dr.Pecker said:
That's one way to do it. Seeds are generally 20% more vigorous growing than a clone but you have to create a large root system. I do this by planting them deeper after they stretch. If it were me I would only run a clone in a hydroponic system This way you can feed them all the same and you know what you're growing because you've grown the seedling/mother. I'm not saying it cant be done and It's good that somebody has tried it. I wish you guys luck.
Click to expand...
I can't watch the video right now, but I will later.

I'm running a SuperCloset SuperStar, hydroponic system. My impression based on what you've said is that the system is designed around clones. You purchase clones and root them in rockwool cubes, then once a root system is formed in the rockwool cube, the cube is transfered to the hydroponic system. I'm not doing this though. I'm starting with a seed, planting it in a rockwool cube, anticipating that a root system will form, such that I can move the cube into the hydroponic system.

I feel I'm at a crossroads. Either I need to start growing seeds in Rapid Rooters and then transfer these Rooters to the hydroponic system once a root system forms, or purchase clones and attempt to root them in Rockwool cubes. Would you agree?

I'm attempting My second grow and currently it has been dismal. I'm only able to produce a single tap root for each seed I plant in Rockwool. I'm not establishing an extensive root system required to transfer the plant to the hydroponic system. Something is incorrect with my process and I desperately need help correcting it.
 
Dr.Pecker

Dr.Pecker

Well-Known Member
Mashkiki'inini said:
I can't watch the video right now, but I will later.

I'm running a SuperCloset SuperStar, hydroponic system. My impression based on what you've said is that the system is designed around clones. You purchase clones and root them in rockwool cubes, then once a root system is formed in the rockwool cube, the cube is transfered to the hydroponic system. I'm not doing this though. I'm starting with a seed, planting it in a rockwool cube, anticipating that a root system will form, such that I can move the cube into the hydroponic system.

I feel I'm at a crossroads. Either I need to start growing seeds in Rapid Rooters and then transfer these Rooters to the hydroponic system once a root system forms, or purchase clones and attempt to root them in Rockwool cubes. Would you agree?

I'm attempting My second grow and currently it has been dismal. I'm only able to produce a single tap root for each seed I plant in Rockwool. I'm not establishing an extensive root system required to transfer the plant to the hydroponic system. Something is incorrect with my process and I desperately need help correcting it.
Click to expand...
You should grow the seedling in soil and when you get more branches then just take cuttings off it to do your hydro garden. i dont use rockwool for seedlings I use starter mix then transplant to soil.
 
F

Fly-high

Member
So I'm just a new guy myself and don't have much experience but I used rockwool for my seeds and it worked out ok. The biggest issue I had was my lack of experience. I just put my small rockwool straight into my net cup and covered with hydroton. Seemed to work beautifully. I might suggest using a T5 for the veg, you can have the light an inch away without having to worry about heat issues and it reduces stretching. I'm using a SuperCloset Deluxe LED and am coming to the end of my first grow. Definitely not trying to act like I know a lot but I do know what I've already experienced.
 
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