Starting seeds in rockwool. What am I doing wrong?

Ok so I germ my seeds with the paper towel method.

I pour 2 cups water into a pitcher, put .25ml floramicro and .5ml florabloom. This ups the ppm from 110 to 510. I then ph down the water to 5.8 and put in .125ml superthrive and then I soak the cubes until their about 6-8 times their normal weight.

I put these in a tupperware container and put the lid lightly over them. And throw them under 600w MH dimmed to 60%

Well 5 days ago I planted 3 seeds. 2 days later they're sprouted, some still have some seed casing closing up the cotyledon's on two of them, one actually opened up and its first set of leaves came up also. I sprayed them 2 days ago(a day after they sprouted) with the same nute solution and I check today(couldn't get a chance to check them yesterday) and the 2 that had the cotyledon's closed up are drooped over the RW and still closed up, they look sad and like their root didn't even penetrate the RW. The one that had its first set of leaves is drooped over now also.

Is this because the RW was kind of dry after not checking it for 2 days? I fed them more today, hopefully they spring back.

I'm trying to follow as much advice thats out there, and theres a ton. I just cant get it to work?

These seeds taproots get to be about 3/8-1/2" long before I get to put them in the RW, could this be the problem?

Hopefully someone can steer me clear on what im doing wrong. They don't look happy at all. They did at one point though, so something was done right.

pre-soak the RW in ph 5.5 water for 24 hours prior to putting seedlings in them (DO NOT PUT NUTES PERIOD) now in the paper towel when the seeds crack open they have a little tail (taproot) on them put them in the cube at that point (tail/taproot down) and under light until they pop up and out the RW. dont water RW again until it is quite dry and light to pick up. your burning them up with nutes before they even have a chance to establish.

Yeah the first set of three I didn't use nutes. When I added water to the RW after they got dry I added nutes. Maybe this is why they looked fine up until I did that.

Some people say 1/4 strength nutes for seedlings. Some dont. I'm just not going to anymore. At around what point do they need them? I figured as long as they had roots theyd use it.

So you know why the cotyledon's are caught up with the seed? Seems they cannot break thru that casing. It looks like theres sets of leaves sandwiched between the closed cotyledon

I don't fertigate until after week 2, sometimes longer. Just because a baby has a stomach doesn't mean we give them adult sized portions. Do an experiment and see how long a seedling will go before it begins to yellow (first sign should be N def). My guess is that would be around week 3 or so.

some seed casings are a little tougher than others. scuffing them with a little sand paper before germination helps.

good luck!

Yes I heard some growers use a file for the edges of the seed. I'm definitely going to experiment on some bag seeds.

Is there a chance of recovery? The tops are tilted over and very defeated looking. And is there anything that can be done. I've tried very carefully with tweezers to remove but to no effect other than chipping a bit off. Then I got nervous so I stopped. One sprout is still standing straight up.

I put some fresh ph 5.7 water into it today to try and flush out the nutes. Hopefully that helps.

Thanks for your advice

Don't give seeds nutes.. I don't feed my seedlings for at least week. Plain ph'd water.. distilled if you have to.

7.0 PH distilled works until you need to add nutes.

Good to know. Its weird because some mods even say nutes on seeds aren't bad. So I thought it wouldn't hurt, i was obviously very wrong, haha. Expensive mistake if those seeds dont make it, but a mistake that won't ever be made again.

No nutes. Soak cubes for atleast a few hours. Wouldn't the cubes be too wet at that point? And I should be adding water not to the top of the cube but to the bottom of the tray so they can suck it up? Im using a humidome.

firsttimeARE said:

Good to know. Its weird because some mods even say nutes on seeds aren't bad. So I thought it wouldn't hurt, i was obviously very wrong, haha. Expensive mistake if those seeds dont make it, but a mistake that won't ever be made again.

No nutes. Soak cubes for atleast a few hours. Wouldn't the cubes be too wet at that point? And I should be adding water not to the top of the cube but to the bottom of the tray so they can suck it up? Im using a humidome.

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When the cubes are removed after soaking lightly squeez the excess water out or hold em and simulate throwing them to flick the excess out but do this in the bath tub. I use a tiny amount of Fox Farm big bloom with my 5.5 ph'ed water.

I heard when you squeeze them you remove all the natural air pockets inside the rockwool, which isn't good. I've also heard salad spinners make quick work out of it. I'm going to invest in one of those tonight.

I've tried the flicking/throwing technique, it works, but is very time consuming.

Im going to do some tests on some bag seeds today.

After humidoming them they sprang back up. One of them did anyways. The one that actually broke the husk died and was brown when I checked them yesterday. The 3 new seeds are sprouted, all 3 broke the husk and shooting off their first set of new leaves.

5/6 alive. I'm going to try and remove that bit of husk on the first 2.

firsttimeARE said:

No nutes. Soak cubes for atleast a few hours. Wouldn't the cubes be too wet at that point? And I should be adding water not to the top of the cube but to the bottom of the tray so they can suck it up? Im using a humidome.

Click to expand...

Wow I only prerinse my cubes, but I use Grodan. I'm not sure about other brands..

I also water from the top by hand until they're showing me a root at the bottom, then it goes into a DWC.

VoidObject said:

Wow I only prerinse my cubes, but I use Grodan. I'm not sure about other brands..

I also water from the top by hand until they're showing me a root at the bottom, then it goes into a DWC.

Click to expand...

That's all I did for these first 6 was a quick dip on all sides in the superthrive and water mix I made. They ended up being 30to35grams in weight from the 5g they start off being.

I then pour the rest of the water in the bottom of the humidome and put the cubes on the raised portions. I flush new water thru them every few days and put new water on the bottom of the humidome. Seems to be working well for the seedlings. I think I'm going to get some perlite for the bottom of the humidome for next time.

I'm putting them into 6inch net pots with grorocks around the RW once I see roots out the bottom. Then they will be going into my ebb&flow setup. Not sure if I should put grorocks in the tray also. Some recommend this so the roots can contiue growing rather than getting air pruned

just keep it simple m8

ive done it this way for many years and not had a problem

make sure the cubes are totally wet soak them under water so they are full of water
put them in a propagator with some water at the bottom or a plastic box or whatever
place the seeds sideways on the cubes, make sure you push them slightly onto the cube so it touches the rock wool but doesn't go under the surface of the cube
put the propagator is a dark place, warm helps but doesnt matter, at room temp they will germinate in 2-4 days, i tend to leave them in the dark in a cupboard for 3 days
they will crack and the tap root will show, i leave them until the tap root is about half a cm or slightly bigger, and place them inside the cube tap root down, with the little seed case poking upward, but none of the tap root showing , i then put them under the light over the next 2 days or so, the shell cracks and the seed leaves pop out

You are probably just overwatering them. Don't freak out too much, seeds and seedlings are very fragile and sometimes they die. It happens.

Yeah i'm calm now...I lost one. She was all brown so I had to chuck her as I was sure she wasn't going to make it. I stunted the first 3 though they're like half the height as the second 3 I planted 5 days later.

Is there a way to get them all even? They're all feminized seeds of the same strain and I don't want to flower some shorter than the others, or worse let the first 3 get to where they need to be and by that time the second set of 3 are huge and will grow too big for my tent.

One is showing some yellowing mid leaf. Going to check today. And another has some grey tint to the ends of the of their first set of real leaves. Only on one side.

At about what time should I remove them from the humidome?

you can put a little bit of nutes but not so much as you did, certainly not 1/4 strength.

wash the cubes with water alone, this is the only chance right now, they will probably die.

firsttimeARE said:

Yeah i'm calm now...I lost one. She was all brown so I had to chuck her as I was sure she wasn't going to make it. I stunted the first 3 though they're like half the height as the second 3 I planted 5 days later.

Is there a way to get them all even? They're all feminized seeds of the same strain and I don't want to flower some shorter than the others, or worse let the first 3 get to where they need to be and by that time the second set of 3 are huge and will grow too big for my tent.

One is showing some yellowing mid leaf. Going to check today. And another has some grey tint to the ends of the of their first set of real leaves. Only on one side.

At about what time should I remove them from the humidome?

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You can't do anything about it until they grow out into full plants. After they get 3-4 nodes you can top the ones that are growing faster. Also you can manipulate the plants location in relation to the light. Move the short plants into the center so they get the most light and then move the larger plants to the outside. Later on you can also LST.

CEEJR said:

When the cubes are removed after soaking lightly squeez the excess water out or hold em and simulate throwing them to flick the excess out but do this in the bath tub. I use a tiny amount of Fox Farm big bloom with my 5.5 ph'ed water.

Click to expand...

If you do that, you will damage the rockwool and mess up the ratio of air to water. Use a salad spinner to remove extra water.

I pre soak the RW cubes for 24 hours, spin them dry with the salad spinner. Then I use a digi scale and a spray bottle to water the cubes to 20g wet. Since I live in a dry climate, I have to water twice daily or the cubes will dry out.

I started placing the seeds directly into the cubes and have had much better results than using the paper towel method.

I put the cubes with seeds in them under my humidity dome with my clones. Once they sprout on the second or third day I take them out of the humidity dome and put them on a tray for about two weeks. I water them everyday with the scale and spray bottle.

Like others have said I do not use nutrients for the seedlings.

I see we both follow Al B, Goldowitz. On page 65 of Al B. Faqt. By the time I finish i'll be moving on over to his starting clones in RW thread. I learn so much every time I visit his threads. I have a notepad document all about the information I pull from it for easier reference in case I forget, which I know I will as i'm taking in a lot.

I bought a salad spinner over the weekend, haven't tried it out yet.

I'm now using a digital scale to weigh the cubes as I use a pipette to measure how much water it takes to get them 4-5 times as heavy. This way i'll have a milliliter number to work with. Going to soak cubes from now in for 24hrs in 5.0 water to offset the lime from production thats left in the grodan.

I had the humidome over for about a week before I took it off. But I think I kept it in too long.

I heard of people filing their seeds down and placing them on their side inside the RW, I haven't tried it yet, but I got some bag seeds I can run a test on to see if it helps the sprouts shed the husk. Got 2 brown spots on the tips of the cotyledons from the husk sandwiching them shut for the first 3-4 days of the sprouts life. I think its because the nutes stunted the plant and it didnt have enough energy to break the husk. It produced real leaves inside too, was definitely closed for a while.

Yes, ABF is a great wealth of information. I have been following his posts for years. I modeled my entire grow after his, but made small changes to suit my style better.