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Rockwool starting and growing

I've never actually started seeds using rockwool before, typically I just start the plants in dirt and wash it off when I move it to hydro.  I have some select varieties I'm starting directly in rockwool this year and was wondering about what kinds of steps I need to take from germination to putting in the Dutch buckets.
 
I started seeds for Bhut Jolokia white, Carolina Reaper, 7 Pot Brain Strain yellow (a very stubborn strain for me this year), and 7 Pot Merlot directly in rockwool.  I pierced through the starter cube with a kabob stick and hollowed out the top half inch with my pinky, I've got germination so far on all of them except the Brains, which is par for the course at this point XD.  The Merlots will be spreading wings probably by tomorrow and I'm wondering at what point do I start giving them something other than the plain well water?  I have Fox Farm Grow Big, General Hydroponics CaliMagic, and fulvic acid that I typically use in buckets mixed with fish water and I'm wondering at what point I should start giving them a diluted feeding in the cube.
 
They're inside of quart take-out soup containers (ghetto domes) at the moment two cubes per container, warming on top of my T5s at a steady 85º
 
So I should just pop them in the Dutch buckets and do like a 1/4 strength feed once the root is through? Seems pretty simple...I might be ahead of myself, i'm not ready for my buckets yet O_o
 
So far what I don't like about rockwool for aeroponics is that it holds water for too long.  I currently have my pump set to turn on for only 15 mins per day.  Any more than that and the plants start to show signs of over watering because that rockwool never drys enough to let air in.
 
Gomojoe said:
So far what I don't like about rockwool for aeroponics is that it holds water for too long.  I currently have my pump set to turn on for only 15 mins per day.  Any more than that and the plants start to show signs of over watering because that rockwool never drys enough to let air in.
I only watered them once when I set the seeds, the rest is just residual from the ghetto takeout container domes.  It's not honestly very wet, I almost wouldn't tell it's moist until I touch it.  I got some extra air pumps today since I have 7 Pot Merlots rearing to go.
 
Are you guys sure I can't keep them in the rockwool for a while longer?  6-8 leaves even?  It's not a matter of "omg I wanna get these guys going" it's more of a matter of "omg I don't have room to have DWC buckets running right now"
 
you can see in the most recent picture on page 2 of my glog where I already have wings XD
http://thehotpepper.com/topic/45192-ikeepfishs-2014-grow-loggrowth-spurts/page-2
 
I'm no expert, but my experience thus far has said that the rock wool keeps too much water, to little O2, thus not the perfect medium. Just my opinion though!
 
Gomojoe said:
I'm no expert, but my experience thus far has said that the rock wool keeps too much water, to little O2, thus not the perfect medium. Just my opinion though!
Understood...do you use aeroponics for growing until they are adults too?
 
What medium would you recommend?  I know the guy at the hydro store was trying to push some sort of bark based plugs on me.
 
Actually, one of the benefits that rockwool sellers hawk is that they don't hold too much water.

I grow in aerponics and the nutrient pump runs 24/7 keeping the rockwool wet constantly and have no problems with overwatering.
 
willard3 said:
Actually, one of the benefits that rockwool sellers hawk is that they don't hold too much water. I grow in aerponics and the nutrient pump runs 24/7 keeping the rockwool wet constantly and have no problems with overwatering.
I must be using different stuff.  The rockwool I'm using holds water like crazy and gets way heavy and doesn't dry out very quickly.  I switched to using plugs similar to the root riot ones which dry out much more quickly.  I'm hoping that once more root is hanging out of the rock wool I can increase the pump time on the rockwool plants though.

My plants were all yellowing, showing signs of over watering, until I dropped down to only 15mins a day and they all greened up and look great.
 
I am using rockwool this year to germinate and grow in. I have several wilds, superhots, and hots growing. What I have been doing is once the seed sprouts (not just hooks, but actually sprouts) I'll leave it in the cube (I'm using the 1"x1"x1") and put it in a tray under the T5's. I leave about 1/4" water in the bottom of the tray so the cube can soak up what it needs and also to keep it from drying out. I made the mistake of not leaving any water in the tray and when I came to check on them 2 days later, the intense T5 light plus the fan running for 1 hour and off for 45 mins then on again, the poor plant was dead as could be and the cube was dry as a bone.

As for how long to leave the plant in the cube, I'm not very experienced with rockwool but I have been letting them grow in the cube until there's 2 set of true leaves. I have found that by that time, the roots have pretty much filled the inside of the small cube. I then just transplant the whole thing into my 1 gallon pots.

Again, this is my first time using rockwool, but what I wrote is only what has been working for me so far.
 
I used rockwool in my aerogarden to start seedlings. Set it for the usual pepper setting and they grew really well. I left them in way to long and was a PITA to get them thru the little holes to transplant them into my soil pots. They are doing fine after the transplant. Had no issues with over-watering using it in the aerogarden.
 
coheed196 said:
I am using rockwool this year to germinate and grow in. I have several wilds, superhots, and hots growing. What I have been doing is once the seed sprouts (not just hooks, but actually sprouts) I'll leave it in the cube (I'm using the 1"x1"x1") and put it in a tray under the T5's. I leave about 1/4" water in the bottom of the tray so the cube can soak up what it needs and also to keep it from drying out. I made the mistake of not leaving any water in the tray and when I came to check on them 2 days later, the intense T5 light plus the fan running for 1 hour and off for 45 mins then on again, the poor plant was dead as could be and the cube was dry as a bone.

As for how long to leave the plant in the cube, I'm not very experienced with rockwool but I have been letting them grow in the cube until there's 2 set of true leaves. I have found that by that time, the roots have pretty much filled the inside of the small cube. I then just transplant the whole thing into my 1 gallon pots.

Again, this is my first time using rockwool, but what I wrote is only what has been working for me so far.
What kind of feeding are you giving your plants?
 
I'm using the 2X2X2 cubes
 
ikeepfish said:
What kind of feeding are you giving your plants?
 
I'm using the 2X2X2 cubes
I have been alternating between Botanicare Pure Blend Pro Grow and kelp4less.com 20-20-20. Then I'll add either Cal-mag or Botanicare Fulvex along with it.

I am not very good at keeping up with how many times a week or anything like that, I just kinda wing it
 
I used Rockwool for the first time this year, mainly for wilds. These are just a few observations,
 
Rockwool for germination
 
A couple of observations on using Rockwool for germination etc. It`s a very good medium overall, but with a few small drawbacks.
 
If you buy the sheets, leave the sheet intact. Separating the individual blocks gives all sorts of problems with trying to keep the level of dampness constant. If you leave the entire block intact and put it in a standard size seedling tray (with no drainage holes), keeping the dampness both reasonable and constant is extremely easy to do. 
 
You will get more helmet-heads than soil, especially from very small seeds, such as C.lanceolatum and C.rhomboideum. 
 
The seedlings tend to get leggy and grow much more slowly, regardless of the intensity of light you give them. They need to be fed very early. I`d recommend at the point of the first true leaves. I found that 1/10 the normal concentration of ferts helped enormously. 
 
When you transplant into soil, you will get lots of algae formed on the rockwool. You then need to balance the watering schedule very careful at first, to avoid damping-off fungus also growing with the algae. 
 
If your plants do not have roots through the bottom of the block, they will dry out in a few hours after transplanting to soil. Do not leave them long between slight watering of the rockwool block.
 
Nigel said:
I used Rockwool for the first time this year, mainly for wilds. These are just a few observations,
 
Rockwool for germination
 
A couple of observations on using Rockwool for germination etc. It`s a very good medium overall, but with a few small drawbacks.
 
If you buy the sheets, leave the sheet intact. Separating the individual blocks gives all sorts of problems with trying to keep the level of dampness constant. If you leave the entire block intact and put it in a standard size seedling tray (with no drainage holes), keeping the dampness both reasonable and constant is extremely easy to do. 
 
You will get more helmet-heads than soil, especially from very small seeds, such as C.lanceolatum and C.rhomboideum. 
 
The seedlings tend to get leggy and grow much more slowly, regardless of the intensity of light you give them. They need to be fed very early. I`d recommend at the point of the first true leaves. I found that 1/10 the normal concentration of ferts helped enormously. 
 
When you transplant into soil, you will get lots of algae formed on the rockwool. You then need to balance the watering schedule very careful at first, to avoid damping-off fungus also growing with the algae. 
 
If your plants do not have roots through the bottom of the block, they will dry out in a few hours after transplanting to soil. Do not leave them long between slight watering of the rockwool block.
I don't intend to transplant any of them into soil, but that's good information to have in case I decide to downsize my amount of buckets (not likely).  This is very helpful though, I'm trying to avoid helmet heads by brushing the rockwool over the dent I put in it, seemed to work with the Merlots.  1/10 sounds like it would be good, I know they aren't pulling any nutes from the rockwool but won't need it until they make leaves.  FF Grow Big is 3-2-6...I'm wondering if at this point I should be putting in the other food I have I'm using on my overwinters that's 8-0-0 with the Grow Big.
 
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