Which mix for regular containers?

[rnewste]

Blue,

You need to do your Math again. You are simply looking at a relative NPK ratio of the native Potting Mix, vs the trace elements of fertilizer that they add. You need to run your calculation on VOLUME.

Example: in my combo mix where the potting mix makes up just 50% of the VOLUME, I add in 3 Cups of tomato fertilizer. This equates to 100 times the trace VOLUME of fertilizer inherent in the Miracle-Gro Potting Mix. NPK numbers on the bag, and the fertilizer box have no relative relationship - - it is the VOLUME of the fertilizer that is important.

Raybo

[Blueaussi]

Originally Posted by rnewste

Blue,

You need to do your Math again. You are simply looking at a relative NPK ratio of the native Potting Mix, vs the trace elements of fertilizer that they add. You need to run your calculation on VOLUME.

Which is what I did. What's the NPK of the tomato formula that you're using?



And, you know, remember...aphids.

[rnewste]

Blue,

I have a simple analysis you can work through. Let's assume the Miracle-Gro added fertilizer is an NPK of .3-.4-.6. Let's use the "New" Tomato-tone as a reference which by the way, has an NPK of 3-4-6. Based on the logic you used, the Potting Mix would contain one-tenth the amount of fertilizer as the Tomato-tone. Right? Your quote below:

""Well, no, more like 10 times less then the NPK ratio of most of tomato fertilizers. Plus, consider that when you put your fertilizer of choice in a container, it is then slowly diluted by the amount of soil in the container.""

As an experiment, fill a measuring Cup with one cup Tomato-tone and set it on the table. Next, fill another measuring Cup with one cup of the Miracle-Gro Potting Mix. What you are claiming is that if one slowly emptied out the cup of Potting Mix and could retrieve the fertilizer it contained, that you would have harvested one-tenth of a cup of pure fertilizer in the Potting Mix, equivalent to 10% of the Tomato-tone sitting in the adjacent Cup.

Conclusion: The NPK Analysis on the package of Tomato-tone has NO relationship to the trace amounts of fertilizer in the original Miracle-Gro Potting Mix. Case in point, what if I add one Cup of Tomato-tone into a Container that holds 1 cubic foot of the Miracle-Gro Potting Mix. What then is the NPK ratio? OK, then what if I add TWO Cups of Tomato-tone? Oh, and while I am at it, what if I add THREE Cups, which is what I recommend in the EarthTainer Mix.

Do you see my Math here, that going only by a plain NPK number does not give you any insight into the RATIO of the original fertilizer that comes in Miracle-Gro, versus the amount of, in this example, Tomato-tone that you added. The important metric here is the variable VOLUME of the fertilizer.

I maintain that with my 3:2:1 "Raybo-Mix" using 1.5 cubic feet of Miracle-Gro, and adding the Bark Fines, and Perlite; then adding 3 Cups of Tomaten Dunger, the ratio of 100-to-1 is much closer to reality, than your calculation of 10-to-1.

In any event, whatever trace amounts of the Miracle-Gro fertilizer will surely be expended within the first 3 months of its use. So over a multiple year useful life, the Potting Mix will contain only the fertilizer that you have added by choice. My goal this coming year will be to blend my own from scratch, as I now have a good database of what works well for tomatoes and peppers.

Raybo

[creister]

Well, I think what I am going to do is use the following mix and see how it works. 3cu ft. pine bark fines
1 cu. ft. peat moss
1 cu. ft. perlite
5 gallons vermiculite

[rnewste]

creister,

Personal opinion, but I think you are way to heavy on the Vermiculite amount, as well as the bark fines. Even Pro-Mix BX contains only 6% Vermiculite. The plants I am trialing in a 3:2:1 ratio of Bark Fines, Potting Mix, and Perlite are quite stunted.

I would recommend more Potting Mix (peat moss) in your composition.

Raybo

[creister]

I'm glad you caught my vermiculite miscalculation, that is far too much. Based on your info, I will rethink.

So you just mix together regular potting mix with perlite and bark fines? I saw your picture of CP in this mix. Do you think that would do well in a regular container (watering from top, drainage holes in bottom) as well?

[rnewste]

Originally Posted by creister

I'm glad you caught my vermiculite miscalculation, that is far too much. Based on your info, I will rethink.

So you just mix together regular potting mix with perlite and bark fines? I saw your picture of CP in this mix. Do you think that would do well in a regular container (watering from top, drainage holes in bottom) as well?

There are so many "variables" here (your local rainfall, temps, humidity, etc.) that I hate to generalize. All I can do is post my results in the EarthTainers and EarthBox trials that I am doing - then folks can draw their own conclusions.

I would suggest you trial for yourself, a couple of different ratios to see which works best in your locale. I would start with about 50% Potting Mix (or Sphagnum Peat Moss) then something less than that percentage of Bark Fines, and then an even lower amount of Perlite plus Vermiculite to round it out.

Remember, aeration is key to container gardening whether a conventional top watering system, or a SWC. Ole "Earl" taught me that several years ago.

Raybo

[creister]

Raybo,

Do you add any lime, gypsum, or dolomite to your containers? Do you do the fertilizer strip, or do I remember that you said you actually spread the fertilizer around the entire edge of the container?

[rnewste]

creister,

I add 3 cups of Dolomitic Lime about 5" deep (when filling the 'Tainer), plus 1 cup starter fertilizer (E.B. Stone) and trowel it all in.

After filling the rest of the 'Tainer with Mix, I then add two strips about 2" below the top surface, using one cup of Tomato Fertilizer per strip. See the latest Rev 1.8 Construction and Planting Guide.

See this direct link to it:

http://earthtainer.tomatofest.com/pd...tion-Guide.pdf

Raybo

[Don S]

I have been using straight Fafard mix in homemade earthboxes (2 tomatoes per), seems to work ok, although I may add more coarse vermiculite next season.

Last year I tried some coconut coir in 5 gallon buckets (1 tomato plant) and that seemed to work ok as well.

[jackdaniel]

I've read of MANY mixes, some I'll list below. My favorite is in the below range:

60% peat moss or coconut coir
20 Perlite
20 Compost

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Basic Soilless Potting Mix
4-6 parts Sphagnum Peat Moss
1 part Perlite
1 part Vermiculite

Basic Mix with Compost
2 parts Compost
2-4 parts Sphagnum Peat Moss
1 part Perlite
1 part Vermiculite

Basic Mix with the Addition of Nutrients
Add ½ cup each per every 8 gallons of mix:
½ cup Bone Meal(Phosphorous)
½ cup Dolomitic Limestone (Raises soil pH and provides calcium and magnesium)
½ cup Blood Meal or Soybean Meal or Dried Kelp Powder (Nitrogen)

---

Seedling mix for seedlings in styrofoam flats :

* 2 parts compost
* 2 part peat moss or coir
* 1 part perlite

The second recipe is a soilless recipe based on the Cornell Mix concept; the third is a classic soil-based formula.

Organic substitute for Cornell Mix (large quantity):

* 1/2 cu. yd. Sphagnum peat or coir
* 1/2 cu. yd perlite
* 10 lbs. bonemeal
* 5 lbs. ground limestone
* 5 lbs. bloodmeal

Classic soil-based mix:

* 1/3 mature compost or leaf mold, screened
* 1/3 garden topsoil
* 1/3 sharp sand

Note: This mix results in a potting soil that is heavier than modern peat mixes, but still has good drainage. Compost has been shown to promote a healthy soil mix that can reduce root diseases. Perlite can be used instead of sand. Organic fertilizer can be added to this base.

♪♫♪♫♪♫♪♫♪♫-out mix for growing seedlings to transplant size:

* 6 parts compost
* 3 parts soil
* 1-2 parts sand
* 1-2 parts aged manure
* 1 part peat moss, pre-wet and sifted
* 1-2 parts leaf mold, if available
* 1 6" pot bone meal

Organic potting mix:

* 1 part sphagnum peat or coir
* 1 part peat humus (short fiber)
* 1 part compost
* 1 part sharp sand (builder's)

to every 80 qts. of this add:

* 1 cup greensand
* 1 cup colloidal phosphate
* 1 1/2 to 2 cups crabmeal, or bloodmeal
* 1/2 cup lime

---

For container gardening always start with a good-quality potting soil. Not all potting soils are created equal. Be sure yours is made with well-composted ingredients and holds water while at the same time proves good drainage. If you have a type or brand of potting soil you like you can use it as a base for the recipes below, or start with the basic potting soil recipe if you prefer to make your soils completely from scratch.

TOOLS/EQUIPMENT NEEDED FOR ALL RECIPES
Wheelbarrow, large bin, or heavy plastic tarp in which to mix materials
Large trowel or small shovel for mixing
Bucket for measuring (size depends on amount of soil you make)

BASIC POTTING SOIL
2 buckets good-quality fine compost, any large sticks or clumps removed
(this should smell very fresh and earthy)
½ bucket fine coconut coir (substitute peat moss if you want an acidic potting soil)
½ bucket coarse sand (builders sand)
½ bucket perlite
Optional: add ½ bucket vermiculite for added water retention

For every 5 gallons of mix add 1 cup of mineral powder (Calcium, Phosphorus and Potassium) and 2-3 Tbs of Kelp Meal. If you cannot find a good mineral powder, mix bone meal with a potash source such as greensand.

Mix well and store any unused portion in plastic bags or covered buckets. Do not allow to dry out! The beneficial organisms in the compost need moisture to survive. If your mix is getting dry, spray with a little water to keep the beneficial bacteria alive.

ACIDIC POTTING SOIL
This mix is excellent for Azaleas, Camellias, Rhododendron, Hydrangeas, Evergreens, Blueberries, Raspberries, Potatoes and Strawberries
2 parts potting soil mix
1 part coarse sand or perlite
1 part peat moss
½ part well composted manure

POTTING MIX FOR BULBS
Great for Daffodils, Glads, Dahlias, and all bulbs. Add a little lime to raise the pH for bulbs which prefer an alkaline soil, such as Bearded Iris.
2 parts potting soil mix
1 part coarse sand
1 part fine coir fiber
Bone meal (follow package directions according to quantity)

POTTING MIX FOR CACTUS AND SUCCULENTS
Great for all plants which require a well-drained, coarse soil.
2 parts potting soil mix
2 parts coarse sand
1 part perlite
For additional nutrients add:
Worm castings, 1 cup per 5 gallons of mix
Bone meal (follow package directions according to quantity)

POTTING MIX FOR ROSES
This mix is excellent for all types of roses. If you have a large bush or vigorous climber be sure to give extra feedings throughout the growing season.
2 parts potting soil mix
1 part well-composted manure
½ part good compost
½ part peat moss
1 part perlite
1 cup alfalfa meal and ½ cup bone meal for every 5 gallons of soil, or according to package directions.

POTTING MIX FOR TERRESTRIAL ORCHIDS, BROMELIADS AND FERNS
This mix is great for Cymbidiums, Lady Slipper Orchids, Terrestrial Bromeliads, and Ferns.
1 part potting soil mix
½ part peat moss
½ part perlite
1 part coconut husk chips or medium orchid bark
optional:
½ part charcoal (approximately ½ inch chunks)

SEED STARTING MIX
This mix works well in seed starting trays, six-packs, or peat/coir fiber pots.
1 part potting soil mix
1 part vermiculite

IMPORTANT NOTE FOR ALL MIXES:
Mix all ingredients well and store any unused soil mixes in plastic bags or covered buckets. Do not allow to dry out! The beneficial organisms in the mix need moisture to survive. If your mix is getting dry, spray with a little water to keep the beneficial bacteria alive.