seed starting mix

[jillian]

So I made up my seed starting mix. Peat and vermiculite, 1 to 1 perhaps a bit more peat. Added a little garden tone for fert and beneficial microbes. The recipe I used says to use 1/4 tsp. lime per gallon of peat since peat is acidic. This seems like an insignificant amount of lime, is this enough?? It is espoma and it is granular, looks like mustard seeds.

[RayR]

I agree it sounds like an insignificant amount for 1 gallon. The problem with many of these formulas that you find is they rarely show any data as to what the PH of the final mix is. It's easy to throw inputs together and call it a seed starting mix or a potting soil but if you don't know where you are starting from and what you have in the end it's like shooting in the dark.
You may get lucky and hit the mark or you may be way off for what is optimal for germination and growth of the seedling.
All peat is not the same, depending on what type it is, where it came from and how it was processed. The manufacture may supply what the PH of the peat is on the bag that you bought or they may not. Some peat is just more acidic than others.
The purpose of adding lime is to raise and buffer the PH of the medium to a target range like a PH of 6.5 or so for example. To know how much to add per gallon it's very helpful to have a way of testing the PH of your mix with a PH test kit, PH papers or a digital PH meter.

[Worth1]

You can always do the vinegar baking soda test.

Worth

[RayR]

Originally Posted by Worth1

You can always do the vinegar baking soda test.

Worth

??? How can that test the PH?
How about the old school farmers PH test, taste the soil to see if it's sweet or sourer.

[Gardeneer]

Talking about lime, try Dolomitic/Fast Acting lime. Otherwise it might not be readily effective.

So I made up my seed starting mix. Peat and vermiculite, 1 to 1 perhaps a bit more peat

It sounds like it would retain too much moisture. 20% perlite addition could be helpful. Both peat moss and vermiculite are highly moisture retentive. JMO

Gardeneer

[Worth1]

I have had great success with just peat pellets.
I wouldn't worry to much about it.

Worth

[Worth1]

Originally Posted by RayR

??? How can that test the PH?
How about the old school farmers PH test, taste the soil to see if it's sweet or sourer.

If it is alkali vinegar will make it foam.
If it is acidic baking soda mixed with clean water will make it foam.
If it doesn't do anything it is neutral.

How much it foams will tell you a lot.
It has always worked for me.
It is a ball park way to figure where you are at.

Worth

[RayR]

Originally Posted by Worth1

If it is alkali vinegar will make it foam.
If it is acidic baking soda mixed with clean water will make it foam.
If it doesn't do anything it is neutral.

How much it foams will tell you a lot.
It has always worked for me.
It is a ball park way to figure where you are at.

Worth

I still don't get it. Assuming you could get a potting mix to foam by adding baking soda or vinegar, the ball park can be pretty huge so you could be way off base.
Heck of a lot easier to just test the PH with the right tools.

[Gardeneer]

Not too long ago I bought a pH test kit at Petsmart. It has a range of 6.0 to 7.6 on pH scale. I did some tests before sending out my soil samples. My results were accurate to +/- 0.1.
The kit is called " API pH test Kit" . Cost $15.00 . You can perform over 200 tests with it.
Gardeneer

[Cole_Robbie]

Rarely do I tout expensive products. An $18 bag of dirt sounds ridiculous, but one bag lasts a season or more, and I get nearly 100% germination of my seeds. With expensive hybrid seeds, Light Warrior pays for itself:

[jillian]

Originally Posted by Cole_Robbie

Rarely do I tout expensive products. An $18 bag of dirt sounds ridiculous, but one bag lasts a season or more, and I get nearly 100% germination of my seeds. With expensive hybrid seeds, Light Warrior pays for itself:

Cole_Robbie, what is the list of ingredients and amounts listed on the bag?

Thanks guys, taking it all in. Still have plenty of time to make amendments as I won't be starting til Feb.

[Cole_Robbie]

"Select spaghnam peat moss, horticultural perlite, earthworm castings, granite dust, humic acid derived from leonardite, mycorrhizal and bacterial innoculant, oyster shell for ph adjustment."

I think the humic acid is the most key ingredient. My second choice for a seed-starting mix is vermiculite drenched with compost tea, which I believe to be high in humic acids.

[Aerial]

Has anyone tried seed starting with only vermiculite? Can I keep my seedlings in only vermiculite for a month if I feed them with MG Plant Food every 2 weeks? (Don't want to risk bringing gnats into my study from the commercial mix.)

[Gardeneer]

As far as I know vermiculite is highly moisture absorbing and it expands in volume.
If you have not experienced damping off and gnats, then fine.
If I want to buy seed starter mix , I would rather mix my own with just peat moss and perlite. That seems to be what commercial growers are using.

Whatever works for you then it is all right.

Gardeneer.

[Cole_Robbie]

All the other peat-based mixes I have tried will crust over at the top and keep sprouts from breaking through. That's probably my fault for not keeping a high enough humidity, but it's a lot easier to maintain one environment for both growing plants and starting seeds.

And yes, vermiculite works fine, roots love it. You can use a very diluted MG. They like fish emulsion, too. I start most of my inexpensive seeds in vermiculite. Lately I have been putting a little peat pro mix in the bottom of the cell, then vermiculite on top of that.