Rockwool in Soil Watering Question

mjj123

Active Member
Hello,

I put my rockwool cubes into soil yesterday. The plants were just showing their first few set of true leaves, but have now been stunted for days. I'm hoping putting the cubes in soil and getting the plants outside light helps them start up again.

When I put the cubes in, they were already moist and the soil was too. I watered a little after burying the cube. Do I just water normally now, or does the rockwool require water before the soil is dry?

Thanks
 

weedenhanced

Well-Known Member
Hello,

I put my rockwool cubes into soil yesterday. The plants were just showing their first few set of true leaves, but have now been stunted for days. I'm hoping putting the cubes in soil and getting the plants outside light helps them start up again.

When I put the cubes in, they were already moist and the soil was too. I watered a little after burying the cube. Do I just water normally now, or does the rockwool require water before the soil is dry?

Thanks
Water very little will promote root growth
 

Know One

Well-Known Member
It is best to wait until you see roots sticking out the bottom of the RW cube before transplanting, however, as long as the plant looks healthy it might just be taking a while to acclimate to it's new home. You might want to pull 1 out to see if there any roots yet? You can always re-plant after inspecting.
There are other variables involved like.. When you say you moved them outside, you mean in pots with RW cubes and soil, or straight into the ground?
Do you know what is the NPK value of the soil is?
Did you mix your soil with any other medium like perlite for aeration?
What was the lighting situation prior to moving outside?
Answering these questions will help give a better idea on how to fix the problem.
Peace..
 

mjj123

Active Member
Thanks for the reply.

I put them outside in about 10" diameter pots, the rockwool cubes in soil.

The soil was Miracle-Gro Potting Mix. I think it's 0.21% N, 0.07% P, and 0.14% K based on some website. I mixed the soil with a handful or two of perlite, and had some perlite at the bottom of the pot.

The lighting situation was not a very good one. The last week or so, the plants have had four 23-watt CFL's in desk lamps about three inches away from the tops. I was thinking these lights would be enough to get roots through the cubes, but maybe not? Think this is why growth stopped?

I hope we can narrow down what I messed up. I've been going over it so much, I want to make sure I don't ever make the same mistake again.
 

weedenhanced

Well-Known Member
It is best to wait until you see roots sticking out the bottom of the RW cube before transplanting, however, as long as the plant looks healthy it might just be taking a while to acclimate to it's new home. You might want to pull 1 out to see if there any roots yet? You can always re-plant after inspecting.
There are other variables involved like.. When you say you moved them outside, you mean in pots with RW cubes and soil, or straight into the ground?
Do you know what is the NPK value of the soil is?
Did you mix your soil with any other medium like perlite for aeration?
What was the lighting situation prior to moving outside?
Answering these questions will help give a better idea on how to fix the problem.
Peace..
Why do u want to wait for roots exactly the seed popped its no diff sitting in a pot then not ripping it out is not a good idea could stunt the plant if u break the tap root if I plant my autos I get my jiffy pellet bury it in the soil upto the top of the pellet germ seed in paper towel then put in the pellet that allrdy in the pot if u wait for roots to stick outa the cube then plant the cube the plant will be stressed if it can naturally grow straight down Into the medium less stress bigger better plant more yield fast
 

weedenhanced

Well-Known Member
Thanks for the reply.

I put them outside in about 10" diameter pots, the rockwool cubes in soil.

The soil was Miracle-Gro Potting Mix. I think it's 0.21% N, 0.07% P, and 0.14% K based on some website. I mixed the soil with a handful or two of perlite, and had some perlite at the bottom of the pot.

The lighting situation was not a very good one. The last week or so, the plants have had four 23-watt CFL's in desk lamps about three inches away from the tops. I was thinking these lights would be enough to get roots through the cubes, but maybe not? Think this is why growth stopped?

I hope we can narrow down what I messed up. I've been going over it so much, I want to make sure I don't ever make the same mistake again.
Definitely not less light is better for root development growth will stop when plants r rooting deep if u overwater or 2 much nuts or dmg the root when young will stop growth
Stick finger in pot 2 in down if wet dont water for a little seedling 1 cup poured about 2 inches away from the seedling in a circle is best makes root stretch and seach for moisture in a plants first week it grows downward (roots) more then it grows upward
Also if nuts in soil addin lots of water will release lota nut cripplin ur plants


I would say the root stopped cause the plant had 2 much water and has no need to dig downward in seach of water cause u wetting it plenty
 
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rob333

Well-Known Member
get a spray bottle full of water and use that for the first 2 weeks then give em about 200 300 ml of water and wait for there roots to get nice and thick
 

rob333

Well-Known Member
touch the cube if its dry spray it make sure the soil under the cube stays moist not wet u want them roots to search for water
 

FlashBabylon

Active Member
Also don't worry if growth looks slow at this stage, the plant is putting more energy into growing roots underground than it is leaves above ground. It'll take off once its root system is well established.
 

mjj123

Active Member
Thanks for the replies. Okay so it's looking like overwatering was the main problem.

For the first week or so, when the cube felt very light, I would dip it into a bowl about 1/4 of the way and let it soak up water for 10 seconds or so. Was this way too much? The cubes were quite saturated at that point but not dripping wet.

Also, how long can a plant appear stunted and then still make a recovery? They haven't changed in any noticeable way for a good week now. I'm feeling like they may have decided to call it quits haha. Can the plants make a recovery if they have no living leaves at all? Even the cotyledons seem to be dead or dying.

P.S I'll add rep to anyone that helps, I just don't think I can until I get to 10 messages.
 
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Know One

Well-Known Member
With all due respect to Weedenhanced, we'll just have to agree to disagree. IMO when planting seeds or clones that start in RW cubes, it is best to wait for roots to show before up-planting into any new medium.

Thanks for the reply.
The soil was Miracle-Gro Potting Mix. I think it's 0.21% N, 0.07% P, and 0.14% K based on some website. I mixed the soil with a handful or two of perlite, and had some perlite at the bottom of the pot.
I believe one the problems is that they went from very little light to direct sunlight.
The bigger problem is that you're using MG potting soil. Miracle Grow can work and there are many posts in here about Miracle Grow you might want to check out. It is definitely not the best choice. Is it the 3 month slow release potting soil? It will say this across the front of the bag.
Do you have any pictures? That would be very helpful.
 
Yes, you have probably over watered; get a scale and weigh them daily keep the weight
around 45 grams and they'll do fine.
Don't transplant until you see roots growing out the bottom.
Also read my post on using rockwool cubes.
 

CashCrops

Well-Known Member
With all due respect to Weedenhanced, we'll just have to agree to disagree. IMO when planting seeds or clones that start in RW cubes, it is best to wait for roots to show before up-planting into any new medium.


I believe one the problems is that they went from very little light to direct sunlight.
The bigger problem is that you're using MG potting soil. Miracle Grow can work and there are many posts in here about Miracle Grow you might want to check out. It is definitely not the best choice. Is it the 3 month slow release potting soil? It will say this across the front of the bag.
Do you have any pictures? That would be very helpful.
You are correct, I don't know wanyone who puts clones or seedling in dirt without seeing roots...
 
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