Has anybody experimented with a homebrew starting/potting mix?

[throwaway]

I think I count at least three ongoing threads this year about the perils of bagged starting mixes across different brands. At least a couple seedling wipeouts, and my 2018 season was "bagged" by bad coir. Prevailing wisdom last time I went to town researching the topic was that it's exceedingly difficult to get the right proportions to get the water retention down - my follow on was that there would never be cost savings vs a MiracleGrow without buying peat and vermiculite in industrial quantities. Pro Mix restored my faith in dirt but I do wonder whether trying a homebrew might be worth the effort.

I've noticed a few of the homebrew potting mix blogs call for bark fines or pine bark fines/mulch - but it must be in short supply because I've never seen it in person or an online option to buy. I have a few pine trees that need to be cut back every year or two but I can't imagine that would yield enough and I'm not sure about the equipment needed to de-bark and shred limbs and trunk. Also have an unwieldy volume of leaves every season that I would love to mulch and contribute to a mix, but haven't seen any indications that would be a good idea in a seedling/potting mix.

Any thoughts? Experimenters?

This year I started transitioning to a variation on the 5-1-1 formula, and so far very good results.
I’m experimenting with both ornamentals and veggies.
I found my pine bark fines at a local stone yard/ landscaping contractor after calling all around Jacksonville, so don’t give up looking.
My formula is roughly:
Pine bark fines (5)
Coarse perlite (1)
Coco chips & fiber (1) (after I work apart the compressed bale using hot water)
Cup of pelletized lime
Cup of epsom salt crystals
2 cups dry fertilizer (I used Dr. Earth and Texas Tomato Foods brand)
2 cups worm castings
1/4 cup azomite

Mix all up in a wheelbarrow; dump into fabric grow bags; water it; let mellow for a week or so.

[edweather]

I also use a similar 5-1-1 mix. I just add a little lime and CRF to the bark, peat and perlite. hahaha, had to smile because I just bought the same bags of pine bark that Jane bought. I got them at Liberty Landscapes in N. Jacksonville. By the title of your post I wasn't sure if you are looking for a starting mix, or a general container mix. @throwaway, where are you located???

[throwaway]

Maybe I'm mistaken, but it seems the difference between seed start mix and general potting is the former is more finely screened and has no fertilizer versus the latter having more larger chunks and usually a slow release fert. Anyhow, I've generally started in a potting mix. In NJ. Thanks for the tips, will keep searching for the pine.

[Gardeneer]

Me too. Mix my own, a version of 5 1 1.
For pine bark fine i get pine bark mulch. Both WM and LOWES carry Timberline brand in 2 cubic ft bags. I screen it to get the chunky pieces out. ..then add peat and perlite, fert,..
This mix has good drainage. So it has to be watered more often than , say MG potting mix

[throwaway]

Do you get the pine bark mini nuggets? https://www.lowes.com/pd/Timberline-...ets/1000132101

Guess I didn't look hard enough, but I scoured Lowes just yesterday.

I was so happy to locate pine bark fines as I didn’t want to screen mini nuggets for 50 grow bags worth.
Plus, what the call ‘mini’ nuggets at Lowe’s and HD is the size of tree trunks sometimes.
I do use mini nuggets as a base under my grow pots. I’m getting 3ft cubic bags from the same stone yard as the fines. It costs about 50 cents more a bag but is much more consistently mini sized plus the bags are are bigger.

[edweather]

@PlainJane, Have you ever tried the Super Course Perlite? It's available in Jacksonville.

http://tropicalfruitforum.com/index.php?topic=31514.0

Originally Posted by edweather

@PlainJane, Have you ever tried the Super Course Perlite? It's available in Jacksonville.

http://tropicalfruitforum.com/index.php?topic=31514.0

I have not ... been making do with the coarse grade from HD.
Do you like it better?

[edweather]

Yes, I do like it better. Not exactly sure if it's scientifically better, but the larger size looks better, and there seems to be a bit less dust. I also used the HD product, and will stick with the Hydro Farms product from now on if I can find it.

[nyrfan]

I have used the following modified Cornell Peat Lite Mix in the past:

16 quarts sphagnum peat moss
8 quarts vermiculite
8 quarts perlite
8 TBSP ground limestone
3 TBSP 5-10-10 fertilizer
2 TBSP of 20% superphosphate

Makes 1 bushel.

Use the finer grade of vermiculite & perlite for seed-starting.

You may omit the 5-10-10, superphosphate & instead use a water-soluable or slow-release fertilizer.

For the original recipes see http://www.greenhouse.cornell.edu/crops/factsheetrtings/peatlite.pdf

[AlittleSalt]

Originally Posted by edweather

Yes, I do like it better. Not exactly sure if it's scientifically better, but the larger size looks better, and there seems to be a bit less dust. I also used the HD product, and will stick with the Hydro Farms product from now on if I can find it.

Therm-O-Rock (brand) is also sold as Chunky Perlite. Here is a picture of the difference in size compared to what most brands call perlite. I bought mine from a mom & pop shop. It clearly shows to have much less dust. I also like it better, and cannot prove it to be scientifically better either. I'll do some searching.

[AlittleSalt]

After searching a few sites, I didn't learn anything new about perlite - other than what was pretty obvious. The fine grain perlite is used for starting mixes. The larger chunky size perlite helps with drainage and aeration - one MJ growing site says that it adds insulation (Not sure about that part).

My local hydroponics store went out of business a few months ago, and I already order more stuff than I should online so I’ll probably make do with the Vigro coarse perlite from Home Depot.
If my mix turns out to need more drainage I’ll reconsider, certainly, but so far so good.

[Worth1]

Originally Posted by PlainJane

My local hydroponics store went out of business a few months ago, and I already order more stuff than I should online so I’ll probably make do with the Vigro coarse perlite from Home Depot.
If my mix turns out to need more drainage I’ll reconsider, certainly, but so far so good.

I use the same stuff with no problems at all and a wet it with a water hose to keep down dust.