Has anybody experimented with a homebrew starting/potting mix?

[JosephineRose]

Once I started paying attention to price, I started making my own seed start and potting up mix. Haven't graduated to my own container mix yet but it is coming. I have played with a coir/peat combo for giant grow bags on onions only. I need to get my compost bin at the new house really singing and then I will try my own mix.



Generally I have found the coir very drying to my plants and also causes them to yellow. I have yet to have a good experience with it as a primary medium.



I buy the sunshine organic peat moss by the bale at home depot and one bag giant of Vigoro perlite and one of vermiculite. I always have a bag of worm castings around. I buy these once every two years or so and it lasts me forever. Costs less than $60 out the door... the seed starting mixes alone are $8-9 for a small bag.



My seed mix is 5 parts finely sifted peat, two parts vermiculite and one part perlite. I find the worm castings in starting mix promotes fungus so I avoid it until the plants are ready to pot up and are seeking more nutrients.



The potting mix is also 5 parts sifted peat (though I use a wider sifting insert on it), two parts perlite, one part vermiculite and 1-2 parts sifted worm castings.

[rnewste]

Over the past 8 years I have experimented with dozens of combo mixes optimized for self-watering containers (EarthBox and my 31 gallon EarthTainers). What I have found to be the best combo mix is a 3-2-1 ratio of Pro-Mix, Microbark, and Perlite.

You want good moisture wicking from the water reservoir without getting the mix too wet. In my experiments, both coir and Vermiculite retained excess moisture which led to root rot. Again, this 3-2-1 ratio is suited to SWC applications, so your own container application may vary.

Here are a pair of Momotaro plants on April 9 in this mix. The plants are starting to flower:




Raybo

[friedgreen51]

We buy mini pine bark nuggets at Lowe's Home Improvement and run it through the chipper/shredder. We take the bag the mini pine bark nuggets comes in and using a bungee cord place it over the discharge outlet of the chipper/shredder and refill the bag with our now pine bark fines. Mini pine bark nuggets were on sale at Lowe's over the weekend 4 for $10.

Also use some Miracle Grow Potting Mix, Black Kow, Peat Moss, and O'Reilly Floor Absorb in my potting mix. The ratio I use is 4 parts Pine Bark Fines, and 1 part each of the above.

[edweather]

I love the chipper/shredder idea.....wish I had one.

[throwaway]

I've contemplated getting that Patriot plug in chipper/shredder. Wonder if it would be up to the task.

On a side note, thanks to everybody for the responses. I'll be hitting this thread for years as a reference.

[friedgreen51]

If you choose to try the pine bark mini nuggets and shred them through a chipper shredder be sure you get the natural non-colored pine bark nuggets. Stay away from the black, red, and brown artificially colored.