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Rockwool blues

I've lost at least half or more of my seedlings that I started on January 4th. (about 20+) Including 5 of my 6 Fataliis. All were started in rockwool and then transplanted up into cups with Pro-Mix BX. I placed the whole cube in just below the soil surface to cure some legginess. They were light starved in the beginning, but then got switched to a south facing window and eventually a mini greenhouse in the window. I thought I was watering them enough as the soil always felt moist and the air was cool and I wasn't getting much evaporation. What I have eventually discovered is that although the soil was moist, the rockwool cube inside it was bone dry. My roots had never made it out of the rockwool and the plant died from lack of water. I think the Pro-Mix had a greater affinity for water and just sucked the cube dry. I subsequently have watered just the cube under the soil of a few plants showing the same symptoms and they immediately recovered. Just thought I would share this info with anyone else using rockwool and water attracting soil. I've always tried to be careful not to over water and instead was doing the opposite. I kept blaming it on lack of light, low temps, wrong nutes, lack of nutes, etc - but it was just simple - no water to the root. Lesson learned.
 
POTAWIE said:
Sorry to here bigT
Your pro-mix was likely too dry and wicked away all the moisture from the rockwool:(

Yah, part of what fooled me is I had a few other seedlings in Pro-Mix without the RW cubes and when those cups felt "light", weight-wise, I watered them fully. The rockwool cups never felt light and were always slightly moist on top, but the cube itself was dry. Most of my watering was bottom watering and I'll bet the water never made it to the cube. Hopefully my pain can be somebody else's gain.
 
Hey Bigt,

I noticed while using rock wool cubes, i got more algae and mold as i transplanted the cubes into bigger pots of coco.. i then started to remove the rockwool from the seedlings before transplant and found much better results for algae and mold control as well as the leggyness ( which i cant explaine because i had loads of light and heat on them, but still a little leggy )

overall i do like using rockwool cubes but will not transplant the entire cube into bigger pots regardless of what i use for the medium.

i think i am going to try something a little different next season... Im going to scrap using rockwool cubes and Jiffy pellets all together and get a really good seed starter mix instead...

i think thats the way to go..

sorry that you got burnt on your seedlings.. try again..
 
I've tried rockwool with peppers and probably did exactly what you just tried and failed. Anyhow, I mailed you some more Fatalli seed on Monday so they should be in your mailbox this afternoon. Trial and error, better luck next time.
 
Rockwool is great for hydroponics, but for just starting regular plants I use pro-mix(or similar) in cells or small pots. Its much cheaper
 
Sorry to hear of your misfortune bigt. It is very nice of you to let us learn from your mistakes too. Thanks for sharing this with us.
 
Pepper Ridge Farm said:
I've tried rockwool with peppers and probably did exactly what you just tried and failed. Anyhow, I mailed you some more Fatalli seed on Monday so they should be in your mailbox this afternoon. Trial and error, better luck next time.

Thanks Cappy! It will be fun to compare how your seeds do against my one remaining Fatalii. January 4th and it's still 2 inches. :lol:

Hotpeppa said:
Hey Bigt,

I noticed while using rock wool cubes, i got more algae and mold as i transplanted the cubes into bigger pots of coco.. i then started to remove the rockwool from the seedlings before transplant and found much better results for algae and mold control as well as the leggyness ( which i cant explaine because i had loads of light and heat on them, but still a little leggy )

overall i do like using rockwool cubes but will not transplant the entire cube into bigger pots regardless of what i use for the medium.

i think i am going to try something a little different next season... Im going to scrap using rockwool cubes and Jiffy pellets all together and get a really good seed starter mix instead...

i think thats the way to go..

sorry that you got burnt on your seedlings.. try again..

I did a 2nd round in rockwool about 2 weeks ago with a heat mat and directly under a two bulb shop light. Zero germination. I got algae this time and didn't the 1st time. Only difference was the light. Way too hot I think. 1st batch in January I had temps at 82F. I moved my one small thermometer to my greenhouse but I'll bet temps this time around with the lights were way over 90F. Like Cappy says, trial and error. I can't blame this on the rockwool as I had great germination 1st time around.

Hotpeppa said:
ill send some more Red Savs if you like ?

I'm good on the Red Savina HP, thanks. They are some of my best seedlings right now. Those and the 7 Pot's (Cappy) are doing well as are almost everything I started directly in Pro-Mix.
 
Even though im concentrating on hydro, i planted too many seeds and some will have to be potted and forced to deal with real nature :-p. Thanks for the warning and hope things work out in the long run. As far as germination i have a red savina hookin that i sowed less than a week ago! but now that im sprouting im scared the rockwool will be nutrient deficient. I'd add a little bit of nutrient, but i don't want to give food for algae and mold. ! WHAT TO DO! I plan on giving a super weak foliar spray when true leaves pop-up
 
Pepper Ridge Farm said:
I've tried rockwool with peppers and probably did exactly what you just tried and failed. Anyhow, I mailed you some more Fatalli seed on Monday so they should be in your mailbox this afternoon. Trial and error, better luck next time.

Fatalii's were in the mailbox. Quick ride up 95 to VA. Thanks for the super fast service Cappy. I'll get them planted tomorrow. I have a few more horses in this race now, I'm back in the Smackdown! :)
 
Cool Tony that is just the way we roll around here. Still plenty of time to have a boat load of Fatalli peppers. You're learning with every mistake.
 
Im using rockwool, but I wait until I can actually see roots from the bottom of the rockwool before planting into a pot with soil. Perhaps you could adopt that method, that way it wouldnt matter as much if the rockwool cube went ultra dry.
 
Sorry to hear about your seedlings BigT,
I usually wait till a few roots are showing and water from the top close to the stem.
just a thought.... I wonder if a sprinkling of those water crystals just round the cubes before you transplant would help????
 
MiLK_MaN said:
Im using rockwool, but I wait until I can actually see roots from the bottom of the rockwool before planting into a pot with soil. Perhaps you could adopt that method, that way it wouldnt matter as much if the rockwool cube went ultra dry.

Yeah, I think that would have worked better, but they didn't seem to be rooting fast in the environment they were in and I thought a transplant to soil would help. This problem just blindsided me.

JungleRain said:
Sorry to hear about your seedlings BigT,
I usually wait till a few roots are showing and water from the top close to the stem.
just a thought.... I wonder if a sprinkling of those water crystals just round the cubes before you transplant would help????

The cubes were well watered at transplant time, I was just slow to diagnose the problem. I have 20/20 hindsight regarding this now.
 
I use rockwool both for hydro and dirt with great success.

As recommended, wait til you see roots in the bottom of the rockwool before you transplant.

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