Sphagnum Peat Moss and Seadlings

Is there any concern with starting seedlings out with Sphagnum Peat Moss? I found a bag of seedling starter and it consisted of Sphagnum Peat Moss, vermiculite, and lime. I read that this medium is considered a soilless medium and that the PH should be between 5.6 and 6.2.
http://www.icmag.com/ic/showthread.php?t=30774&highlight=ph
My runoff tested somewhere at a PH of 6 or below. I am not sure because my tester does not go below 6.

Anyone else starting seedlings out in Sphagnum Peat Moss?

you have to watch that stuff. I used it once ande had a nute lock out because of a PH problem. Wet the mix ,let it stand for a week and then check the PH. If you need to add more lime or not. But straight out of the bag I qould not use again. Vermiculite holds water so I would add about 1/2 perlite to that mix for drainage.

I would add 2 tbls dolomite lime per gtallon soil mix the same way you should with promix

vonforne and SKELETOR,
Thanks for your input I needed that : )

This is what I was afraid of. I already planted the seeds so I am out of luck with the lime. I did not add any lime because the bag said it already contained lime. Maybe the lime just needs to start breaking down before the PH is raised? I am not sure because I have never used lime before. However I have heard that lime is not water soluble so it does me no good to try and dissolve it in water to raise the PH does it? If not I guess I will be getting some more PH up from the pet store.

I do have some dolomite lime but it is not crushed/powdered.

I'd use lime when you tyransplant up a size,you started in a small pot right?Promix says they add lime too,definately not nearly enough lol.

Hard lesson learned, don't use Peat Moss. If someone out there stumbles across this post, take my advise don't use peat moss (just my opinion). I have had really bad PH problems. I cannot get the PH to exceptable levels. This really sucks.

For the life of me I cannot find a good medium to start my seedlings out in that does not have ferts and is PH balanced. Why is this so Fucking hard for me. Once I get my plants past the first 3 weeks they do really well and I have somewhat of a green thumb. Its the first 3 weeks that is a killer for me. Its all because I have yet to find a good medium to start seedlings out in.

make your own. Ph balance it before hand.

tiktok420 said:

For the life of me I cannot find a good medium to start my seedlings out in that does not have ferts and is PH balanced.

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How about coco? It contains no ferts and should be pH neutral.

I start my seedlings out in rapid rooters.

The product description for Fox Farm Light Warrior (a soilless medium) reads:

"...excellent medium for starting seeds, transplanting ..."

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I believe many other companies (including Botanicare, I think) make soilless mixes that are good for starting seedlings.

>How about coco?
>...Fox Farm Light Warrior...
Nearest hydro shop is 30 miles away, and this hydro shop sucks. I am also to paranoid to go more than once or twice a year. But that is a lame excuse isn't it : )

>I start my seedlings out in rapid rooters.
I have never used rapid rooters but I would predict that the seedlings would outgrow one of these in about 1 week. Then what?

tiktok420 said:

I have never used rapid rooters but I would predict that the seedlings would outgrow one of these in about 1 week. Then what?

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After they germinate I stick 'em into 3" rockwool cubes. When the roots start to poke out of the cubes, I move them into their final DWC homes.

For my next grow I'm going to be doing either soil or coco instead of hydro, so I'd skip the rockwool step and stick the rapid rooters into the soil/coco cups.

I use seed starter mix and it works great for me. It's peat, perlite, vermiculite, and a wetting agent. I add a pinch of worm castings to the mix this way seedling won't yellow before transplant.

tiktok420 said:

Hard lesson learned, don't use Peat Moss. If someone out there stumbles across this post, take my advise don't use peat moss (just my opinion). I have had really bad PH problems. I cannot get the PH to exceptable levels. This really sucks.

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If your adjusting water ph or fert water ph after mixing, the peatmoss mixture will rise or lower in ph toward the liquid ph. Some readily available ph adjusters around town are in my signature below how to make your own ph up and down. There should be some dolomite lime in your soilless mixture to get you into the right/close ph range to start.

I'd like to give a different view,you can adjust yur nutrient ph to 9.5 if you want to,its still not going to raise the soil ph of that crap unless you lime it.Thats the only way.this "chasing" of nutrient ph is something I've never experienced and I've been growing a few years.Just add 2 tbls dolomite per gallon soil mix and dont worry about it

There shouldn't be a problem with peat moss and vermeculite or perlite. If you have a drastic PH drift, the cause is elsewhere IMO. Tapwater would be the most likely culprit, luckily mine is close to ideal with a PH range of 6.8-7.0. Extensive troubleshooting on a failed batch of clones revealed the quality of our water, most aren't so lucky.

For seedlings, one of the important finds is soil temp, then seed tray humidity. Soil temp is kept at optimum in seedling trays that hold about 3 tablespoons of peat mix. (I tried different container sizes and found the most consistent successes occurred in small containers.) I use florist seedling trays and a heated tray, filled with my soil-less mixture (same as ProMix without water retainer, lime or other additives.) Peat moss has neutral relative PH (7.0) and will always show that in soil tests, but the runoff will always be lower, usually 6.4-6.8. I mix in cinnamon powder to eliminate risk of damping off. Once sprouted, humidity becomes a priority, along with enough good light to prevent stretching and toppling over.

Keeping it simple insures consistent success rates. Adding lime, ph up or down, etc always led to problems for me. It's a weed, it wants to grow, all we have to do is provide a natural comfortable medium for that to take place. If mother nature wanted lime in the soil she would have put it there. Plants grow perfectly healthy with only the natural organics in a given soil patch at any given time, no one sneaks around adding lime and crap - and if they did they would most likely kill the plant. Peat moss is the ideal germinating medium IMO.

When you find yourself having problems, go back to the basics and you'll find the solution.

PS: Adding lime doesn't make sense when peat moss buffers to 7.0. All it will do is leach organic matter to compost. Lime is an aid to decomposition, why would you want to try to accelerate decomposition of the peat moss medium? IMHO I think the lime wives' tale started with trying to fix bad dirt, and it got carried over to include any potting mixture. Peat moss isn't bad dirt and when drainage enhancements are added nothing else should be needed. Or I've just been lucky in 45 years of growing.

SKELETOR said:

I'd like to give a different view,you can adjust yur nutrient ph to 9.5 if you want to,its still not going to raise the soil ph of that crap unless you lime it.Thats the only way.this "chasing" of nutrient ph is something I've never experienced and I've been growing a few years.Just add 2 tbls dolomite per gallon soil mix and dont worry about it

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You need to read my thread on making your own nutrient solution in my signature. I will quote myself:

A note to soilless media growers using dolomite lime in their mixes for ph control...you would not want to use this nutrient solution because it contains alot of calcium and magnesium that is not required. A way to get around this would be to use very little lime like 1/2 teaspoon to a 6" diameter pot or 2 tablespoons per cubic foot of soil and get the calcium and magnesium through the nutrient solution. Because of national security, we are no longer able to get ammonium nitrate and are forced to get some of the nitrogen from calcium nitrate. So, the trend will be to use little lime.

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1TokeOverLine said:

Peat moss has neutral relative PH (7.0) and will always show that in soil tests, but the runoff will always be lower, usually 6.4-6.8..... Peat moss isn't bad dirt and when drainage enhancements are added nothing else should be needed. Or I've just been lucky in 45 years of growing.

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I think you have been lucky if your not fu#king with us. Peatmoss I get and probably most others has a ph to start at 4.5 or so. You must have some "dope" peatmoss connections. Here is what this website says:

pH is a measure of the acidity or alkalinity of a substance. The pH of different types of peat range from a very acid 3.6 to slightly alkaline 7.5. Two terms are used to describe the pH of peat. Low lime peats have a pH value below 5.0. These peats are usually calcium deficient. High lime peats have a pH above 5.0 and are usually calcium sufficient.

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http://www.peatmoss.com/hortprog1.php

Sproutco you say I need to read whats in your signature,I did man and it was about as helpful as the rest of the bookstuff you spew about ph and such,and you dont even grow MJ??You go around telling people its just fine to have a soil ph below 6 and you dont grow MJ?I've had low soil ph GROWING MJ and I'll just continue to use my dolomite and keep my soil ph between 6 and 7.Not 5.5 or 5.8

Sorry everyone for starting a post that turned into a flame, lets just chill.

I do still stand behind my opinion that peat moss is no good for cannabis. Here is something that makes no sense. People say to add lime to peat moss but lime has nutes in it. Its high in Mg and Ca. How can advise be given telling people not to fert their plants or plant their seedlings in a medium that has ferts in it for the first 3 weeks of the plants life but then say its ok to add lime. I must be completely missing something here. The ph of my peat moss is way below 6. Just take a look at the picture of my seedling. I have had to do some emergency transplanting but the problem is I cannot simply remove the peat moss since the roots are so embedded into the medium. I also included a picture of the peat based medium I thought would be great to start my seedlings in. This stuff really sucks.

tiktok420 said:

Here is something that makes no sense. People say to add lime to peat moss but lime has nutes in it. Its high in Mg and Ca. How can advise be given telling people not to fert their plants or plant their seedlings in a medium that has ferts in it for the first 3 weeks of the plants life but then say its ok to add lime. I must be completely missing something here.

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Not all nutes are created equal. Nitrogen will burn roots MUCH qucker than Ca or Mg. Ca has very low potentail to burn roots but has high buffer capabilities whereas N will burn roots fast and has No buffer capabilities. Mg is a pretty gentle nute also, especially when combined with Ca. Also, Ca and Mg will help turn a soil pH to neutral whereas N alone, P alone or K alone will have drastic pH changes.

Also, I have numerous lab studies showing that peat will decomposose over time and release acids that will indeed drop the pH of the peat.
Premeire hort and Sunshine do not add a bit of lime to their mixes because of wives tales. They are professional companies who have studied peat to death and can produce facts about peat down to the micron.

The Slickster said:

The main problem with peat moss is the fungus gnats,.

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Most fungus gnats problems I've seen have come from peat mixes that were not properly sterilized beforehand, and it's not so much that the adult gnats weren't killed off by the sterilization, it's more so that the eggs were not killed.


The great thing about seedlings is their containers can be so small that's it's not too much trouble to sterilize peat (because of the low volume) using a pressure cooker. Fungus gnats are called fungus gnats because they thrive where fungus thrives, but sterilized peat is not in itself a vector or breeding ground for fungus.