Has anyone found a potting soil without a bunch of mulch, rocks, acorns?

HollowOfWisps

Previously AstroDuck
Aug 28, 2020
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Iowa
I use a soil blocker to start my seedlings, but if there is any mulch or other objects in the soil it can cause the blocks to break. I used to like miracle grow, but these last few bags have been filled with mulch, acorns, rocks and even pieces of shredded plastic. So I am wondering if anyone has found a good potting soil that isn't filled with mulch, rocks, plastic and acorns?😅
 
I've been using Coco Coir to start seedlings. It has nothing else in it, seeds start great, but you need to "feed" them a mild nutrient solution each time you "water" them because it's a soilless mix. I like it a lot for starting seeds but price per brick and quality really varies a lot, like everything else these days I guess. I'm thinking of using coco coir to make my chickens some microgreens during the winter, under my seed starting T5 lights.
 
I start with peat moss. When my bundle of that is gone, I'll be using coir.

1 part peat
1 part compost (my compost, so free for my labor)
some perlite sprinkled over (1 cup to 1 quart, depending on the peat/compost amount)
ditto with vermiculite
sprinkle with organic fertilizer

Mix everything. WEAR A MASK! Peat is very dusty. Spray with water as you mix it, and moisten it as you mix. It will take a lot of water to dampen it, and you'll probably have to do it over hours/days.

Peat is acidic. If you're using this for acid loving plants, it should be good as is. If you think you need to push up the pH, mix in some hardwood ashes if you have them.
 
I use generic potting soil and mix in blood meal, perlite, worm castings and vermiculite. I kind of just eye it, add warm water, and then mix it. I give the blocker a try and if I like how they mold I don't alter it. These did a lot better than those I added cococoir to in holding a shape, but my cococoir ones are pretty solid too.

Definitely cover your mouth. The bloodmeal reeks and is a very fine dust.
 
You don't want potting mix for starting seeds, you want a germination mix.
Also, from what read and seen you don't want your blocks to dry out if the medium dries out it will fall apart.

You could use;

Pro-Mix FPO it only come in 3.8 cuft bags but is designed for plug seed germination and is very fine in texture.

Johnny's 512 mix (what Johnny seeds recommends).

You can mix you own also, Penn State recommended;
30 qts brown peat (standard peat moss)
20 qts coarse sand or horticulture grade perlite
20 qts well-decomposed compost
1 qt garden soil
1/2 cup lime
3 cups base fertilizer (equal parts blood meal, colloidal phosphate, and greensand)

Moisten the mix thoroughly using 1 part tepid water for every 3 parts blocking mix. Successful soil-block making depends on the mix being wet enough. The mix should have the consistency of soft putty or wet cement, so that a small amount of water oozes through small openings in the blocker as the blocks are made, and the individual blocks cling to the blocker until you are ready to release them.
 
You don't want potting mix for starting seeds, you want a germination mix.
Also, from what read and seen you don't want your blocks to dry out if the medium dries out it will fall apart.

You could use;

Pro-Mix FPO it only come in 3.8 cuft bags but is designed for plug seed germination and is very fine in texture.

Johnny's 512 mix (what Johnny seeds recommends).

You can mix you own also, Penn State recommended;
30 qts brown peat (standard peat moss)
20 qts coarse sand or horticulture grade perlite
20 qts well-decomposed compost
1 qt garden soil
1/2 cup lime
3 cups base fertilizer (equal parts blood meal, colloidal phosphate, and greensand)

Moisten the mix thoroughly using 1 part tepid water for every 3 parts blocking mix. Successful soil-block making depends on the mix being wet enough. The mix should have the consistency of soft putty or wet cement, so that a small amount of water oozes through small openings in the blocker as the blocks are made, and the individual blocks cling to the blocker until you are ready to release them.
Thanks for the advice! I think I will order in to my local ACE the Pro Mix FPO and also order a bag from Johnny's to compare the two. I have been blocking for a couple of years now and can get them to stay in the past, but if there is a large piece of mulch or rocks they create weak spots in the blocks that eventually can pull apart especially once the roots set in. I haven't had any issues until this year where seemingly the quality of every brand I have purchased and opened looked like someone's mulch pile with a shovel of soil mixed in. As far as potting soil goes you are correct seed starting mix is better. I usually use seed starting mixes, but this year at least in my area I seem to be paying for a bag of much rather than soil with everything.

This is what I was using, but the quality has definitely gone down hill.
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You could use;

Pro-Mix FPO it only come in 3.8 cuft bags but is designed for plug seed germination and is very fine in texture.

Johnny's 512 mix (what Johnny seeds recommends).

You can mix you own also, Penn State recommended;
30 qts brown peat (standard peat moss)
20 qts coarse sand or horticulture grade perlite
20 qts well-decomposed compost
1 qt garden soil
1/2 cup lime
3 cups base fertilizer (equal parts blood meal, colloidal phosphate, and greensand)

Moisten the mix thoroughly using 1 part tepid water for every 3 parts blocking mix. Successful soil-block making depends on the mix being wet enough. The mix should have the consistency of soft putty or wet cement, so that a small amount of water oozes through small openings in the blocker as the blocks are made, and the individual blocks cling to the blocker until you are ready to release them.
Thank you for posting this!
 
I've been using Coco Coir to start seedlings. It has nothing else in it, seeds start great, but you need to "feed" them a mild nutrient solution each time you "water" them because it's a soilless mix.
What do you feed with and how much?
 

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