I'd say not to over think it.

If it were me, I'd make a small batch and try it out on a small scale before I jumped in with both feet, just in case adjustments need to be made.

I've been able to hunt down pine fines at garden centers that carry bagged mulch. I've even been able to find a reasonable facsimile at Lowe's.

It's a rather forgiving mix and I've personally been very pleased with it.

Good luck
=D

Thanks for the feedback hookilau. Knowing it's more forgiving than I thought makes me less nervous about it. Trying a small batch wouldn't be a bad idea. The only place I've been able to track down anything that sounds like the right pine bark is about 45 minutes away, so that makes small batches a little harder, but maybe I'll try somewhere closer in person instead of by phone and see what they have. Most nurseries / garden centers I've called seem to have little idea of what I'm looking for.

I do need to make my mix pretty soon. In Zone 9 the time to plant outdoors is right around the corner (if not here already). :-)

Hi Josh,

Thanks for the tip. Mostly I was calling nurseries. I did some more calling around (a little farther away) and found a couple of places that might sell it. One has something they refer to as "fine screen" pine bark.

http://cypresscreeklandscapesupply.com/products.html

Not sure how "fine" fine is though. The guy on the phone just told me "it's about the size of a fingertip". I'm a computer programmer, that lack of specificity is driving me NUTS!! :-)

I found another place that sells fine pine bark, but they refer to it as "blueberry mix". I'm concerned there are additives that will make it too acidic so I'll need to check on that in more detail.

Thanks again for the landscape supply suggestion. Definitely a help.

This bark is on the coarse side:
{{gwi:2117708}}
{{gwi:20507}}
{{gwi:20506}}

but it still makes a good soil.
{{gwi:20508}}

The bark at 3, 6, and 9 o'clock will make a 5:1:1 mix like you see in the middle - what I consider ideal.
{{gwi:2389}}

Your mix should be somewhere close to

2 cu ft of appropriate size pine bark fines
4-5 gallons of peat
4-5 gallons of perlite
1-1/2 cup dolomitic (garden) lime

Al

Hi Al,

Thanks very much. Those photos are *extremely* helpful. They'll help me to know what to look for. If I came across a bag of the first I would have discounted it and thought it was far too large to work at all. I'm used to seeing peat based mixes that "look like dirt" even if they have some bark mixed in.

I'm going to try to pick up some pine bark this Saturday. I may actually stop by a few different places and buy a bag or two from each to try and see what works best. Looking forward to growing this year! :-)

So, this reply is a little overdue, but I wanted to wrap up the thread & maybe get some final feedback. This is the end result mix using the pine bark I found. I believe this looks right. It doesn't look as corse as the bark Al used in his photos above, but he said that bark was a little more course than he'd prefer so hopefully the stuff I ended up with is about right. If anyone things I could look for something different/better next time around, I always appreciate the feedback.

This post was edited by CliffPruitt on Fri, Jan 23, 15 at 17:18

It looks pretty darn good!

Those yellow "matchstick" pieces are sapwood, and if you can remove as much as possible that would be best....however, it doesn't look like too much, so it should be fine :-)

Josh

Hi Josh,

Thanks! I wondered about "the sticks" but didn't know how big a deal it would be. I need a lot (16-20 cu ft) of this right now so I don't expect I'll be picking it out by hand, but I might be a little more thorough on some smaller containers. At least pull out the larger pieces.

.This is the pine bark I got. I think it is almost perfect for 5-1-1
I buy them from Lowes. Last time I checked they were cleaned out. I hope they will bring more.
I don't even have to add peat moss to it, just perlite.

Seysonn

I'd be super happy if Lowes here carried it. Nothing even close at ours. I had to drive about an hour to just north of Tampa to find mine, but it was a nursery I'd wanted to visit for a while anyway so it was a nice Saturday errand run. :-)

I'm glad for you guys, and think both of you did well for yourselves. It looks like really nice stuff, and Cliff's soil should perform nicely. Makes me want to GROW something. Several inches of snow on the ground, and some more coming for the weekend, so tomatoes and cukes aren't in the immediate offing.

Al

Al, I gotta say, growing up on the FL west coast I've always had fishing as a hobby, but it's nice to see that living down here has perks for my new interest as well. I just started some tomatoes and peppers (indoor) this past week. Here's hoping for an early spring for you!

Have you considered that you are using a measurement for water for a dry material?

What you are using is what is called "U.S Dry Measure" So if you take your 22.44 measure as water volume, the Dry measurement is only 19.28 dry/gals.

Your bark is the biggest pc's in the mix, thus all other smaller pc's will blend into the air voids of the bigger pc's so your not really gaining on the volume of the finished mix.

I, use a blend similar to what you are using, but my peatmoss came as a pre-mix in 2.8 c/f bags. I would add this to 4 bags of 2 c/f pine bark. But the final volume was only approx. 9 c/f, not 10.8

So if you thinking that the 3 c/f bag holds 22.44 gals. it doesn't, it only 19.28 gals.

To make 21 cu ft of soil, he will need about 9 - 2 cu ft bags of bark + the appropriate volumes of peat and perlite + the lime.

Al

Going back to your question about checking your math, my calculations are that you need at most 10 cups of lime and 10 cups of controlled release fertilizer. With your goal of 21 cubic feet of final mix, you will have 157.5 gallons of mix (assuming a cubic foot of mix is equal to 7.5 gallons). You need 1 tablespoon of lime per gallon. 157.5 tablespoons equals just under 10 cups. Now some will quibble about how many U.S. gallons are in a cubic foot due to dry and liquid measure differences, but this is not "rocket science," so to speak. In any case, I think 15 cups of lime is too much. I usually use a scant 1/2 cup lime per cubic foot

Here are 2 questions from another site from a few years ago, that was asked of me. I, sent the ? to Sun Gro and the following person answered back.

Herbert Rabalais
District Manager
Sun Gro Horticulture

Q. If a 3.8 c/f bag of Peatmoss is compressed, what is the loose equivalant per bag?

A. 3.8 cu ft compressed bale should fluff out to 7.2 cu ft loose

Q. How much dolimite would I, need to raise the PH to 6.5-7.0 per 3.8 c/f bale?

A. peat moss starting pH will vary somewhat and there are numerous other variables however, assuming the starting pH of the peat moss is 4 to 4.5 then 12 lbs/cu yd of dolomitic lime would be a good starting point.

So "Ohiofem" how many cups of Lime equals 12 lbs.??

Thunderbear: I have no idea. I would think different formulations (dolomitic vs calcitic lime, pelletized vs powdered lime) would have different weights per volume and would require different amounts to neutralize the mix. Also, pine bark is the primary component of 5-1-1, and I belive it is less acidic so requires less lime. I am more of a home cook than a soil scientist, so I just follow Al's recipe.

Just popping in... Great info !!

Al, Robin, Josh' ;-)

Looks like great 5-1-1 mix to me!!

Good luck and let's hope for an early spring!!

Laura

Thanks everyone for the additional feedback.

ThunderBear48, Thanks for the info. I had not considered the smaller particles naturally filling in gaps between larger ones, which makes obvious sense in hindsight.

I had realized my mistake in using liquid gallon conversions over dry but realized it after buying the pine bark. I don't think it will affect my end result in this case. My math this time around was mainly to be sure I'd purchased enough materials to fill my planter. I did the math and then bought extra so the only down side in this instance will be less surplus at the end. That said, thanks very much for the correction. I'll be sure to bear it in mind next time. I obviously have a good bit more to learn with regard to calculating volumes in advance.

Some of my math (e.g. the lime) was attempting to extrapolate Al's original recipe into a larger batch. There was some wiggle room in the volumes (e.g. 2-3 cu ft of pine bark) so my amounts may very well be off a bit. When I actually make the mix I'll be doing it in smaller batches and then filling my planter as I go (mixing 20-21 cu ft at once might get a bit unwieldy). When I do I'll be more closely following the measurements used in Al's original "Container Soils" post:

Big batch:
2-3 cu ft pine bark fines
5 gallons peat
5 gallons perlite
2 cups dolomitic (garden) lime (or gypsum in some cases)
2 cups CRF (if preferred)

I am assuming that for convenience Al was referring to a standard 5 gallon bucket worth of peat/perlite and that the mix is pretty forgiving of small discrepancies.

Hopefully this weekend I'll finally have the planter done, filled and ready for veggies added sometime in Feb. Been reading / researching / planning / working on this since the end of last summer. So much to learn through one project!

Unfortunately, when trying to determine how much lime or CRF to use, there is quite a bit of wiggle room between Al's two recipes for 5-1-1 in the original post. The big batch is closer to a 3-1-1 if you use only 2 cubic feet of bark. And in that case, you would be adding 32 tablespoons of lime to 25 gallons of mix. The small batch is actually 5-1-1, and it calls for exactly one tablespoon of lime per gallon of final mix. Quoting:

The 5:1:1 mix:

5 parts pine bark fines (partially composted fines are best)
1 part sphagnum peat (not reed or sedge peat please)
1-2 parts perlite
garden lime (or gypsum in some cases)
controlled release fertilizer (if preferred)

Big batch:
2-3 cu ft pine bark fines
5 gallons peat
5 gallons perlite
2 cups dolomitic (garden) lime (or gypsum in some cases)
2 cups CRF (if preferred)

Small batch:
3 gallons pine bark
1/2 gallon peat
1/2 gallon perlite
4 tbsp lime (or gypsum in some cases)
1/4 cup CRF (if preferred)

I don't really think it makes a lot of difference, but I prefer to use the more precise small batch recipe. And, note that above, Al says:

Your mix should be somewhere close to

2 cu ft of appropriate size pine bark fines
4-5 gallons of peat
4-5 gallons of perlite
1-1/2 cup dolomitic (garden) lime

I've made soils with bark that was fine enough that I added more than 1 part of perlite and less than 1 part of peat, and some sop coarse I added more peat and less perlite. I think I would almost be misleading people if I suggested the recipe for the 5:1:1 mix should be followed closely or it won't work. Ideally, people will gain an understanding of the concept behind the soils and stop adding fine stuff long before all the larger soil pores are full of peat, compost, or other fine particles. The 5:1:1 mix isn't about a magical ratio that ensures success, it's about knowing how to use your resources to build into your soils a much more favorable ratio of air:water - so that excess water retention and the lack of O2 in the rhizosphere that causes isn't as limiting as it is in soils based on finer materials OR a mix that has too many fines for the volume of coarse material.

That's why you can't start with a peat-based soil and effectively amend it with bark and perlite. The bark and perlite needs to be a very large fraction of the soil, (like 75-80%) or the fines will simply fill in the potential air spaces between the larger particles and spoil your efforts.
For the 5:1:1 mix, how you combine the ingredients is a little more critical if you want to get the most from the soil and for your efforts. If the gritty mix isn't screened, I suggest you forget it and go with the 5:1:1 mix, because one of the goals of building the gritty mix is to eliminate as much perched water as possible and still have good water retention. Once you start having to deal with a gritty mix that holds perched water, you've negated the primary reason for making it.

Al

Well, I'm at the point now where I think that, in terms of further learning, making the mix and using it is going to be as beneficial to me as anything else. Without doing it at least once I'm not going to know enough about the interaction between bark and peat/perlite to make any educated guess as to how to modify the recipe for specific granularity of pine bark.

My main concern with this large a quantity would only be in doing something to the soil that makes it absolutely unbearable for the plant (e.g. fertilizing to the point of burning the plants). The amount of wiggle room in the original recipe is what lead me to believe it was a general guide vs. a scientific formula, and probably a pretty forgiving mix to begin with. I'll be satisfied as long as it's a "good" mix that lets the plants grow reasonable well.

I think Al's original post covered quite nicely the subjects of "good", "better" and "best" soils:

"We're only interested in the comparative degrees of 'good' and 'better' here. It would be presumptive to label any soil "best". [...] Let's tackle 'good', then move on to 'better', and finally see what we can do about qualifying these descriptors so they can apply to all growers."

I would think that the original post's recipe, "wiggle room" and all, is a good middle of the road starting point for the 5/1/1 and something that should hopefully give me "better than peat based mix" results, even if my first effort could be improved on considerably. Some of my smaller container plantings will give me opportunity to experiment with some variations on all of this. For my larger container I'm going to try to be practical, middle of the road, and just play it safe. If I just get "good" results, let alone "better", I'll be very happy. (My father in law gets some amount of harvest when planting in his back yard sugar sand. I'm sure I can at least match that!)

This post was edited by CliffPruitt on Tue, Jan 27, 15 at 16:17

CliffPruitt

Which mix are you referring to. He says 5:1:1 But then he changes that to 5:1:2 or 6:1:1.

What he doesn't ever say is what his starting PH is and the ending PH is after adding the Dolomite. If you want to grow Blueberries or Azaleas you can't do that in a sweet soil, but tomato's like it.

PH is important to know for growing different types of plants.

So were is the comments for what you want to do from the start of this thread.

Goal: 21 Cubic Feet

Dolomitic Garden Lime
15 Cups

Controlled Release Fertilizer
15 Cups

You use that much Dolomite you will have a PH off the charts.

You use that much CRF, that's enough to do 5-6 batches of mix.

OH Well, do what you want!!!

pH issue:

Trying to figure out needed lime to raise the pH, solely based on the pH of peat moss is incorrect.
In a 5-1-1 mix the amount of peat moss consists of 15% of the mix, not 100% peat moss. Over 70 % is pine bark which has a pH of near 5.5 to 6 (or in that neighborhood). which most plants can tolerate. The remaining 15% is perlite (Neutral ?) So by adding one TBS of lime per gallon that should take care of.

Seysonn

ThunderBear48,

I had a little bit of a hard time time following you on your last post. It's possible we're emphasizing two different topics based on different parts of the conversation.

Maybe to clarify a bit: As I said in my original post, this is for a vegetable garden which would sort of implicitly exclude azaleas and blueberries. I understand that some species have different requirements but I'm interested in a more or less "generic" mix. My list at the beginning was (as I mentioned in another comment) an attempt to build a shopping list. Accuracy would be nice, but I'm not going to be dumping those amounts into a big bin & mixing at once. Having a surplus is fine, I just wanted to be sure that I didn't have too little to complete the project. I reached 15 cups based on the following (assuming at the time [inaccurately] 15 cu ft of pine bark and extrapolating Al's recipe):

Big batch:
2-3 cu ft pine bark fines
2 cups dolomitic (garden) lime (or gypsum in some cases)

Assuming that I used the least amount of pine bark in the mix (thus the highest amount of lime I'd need):
(15/2) * 2 = 15 cups lime

Obviously, there may be some flaws in the way I reached that number. Since that point, I've learned plenty (much of it from information shared in this thread) so I don't think the original numbers are as relevant as they were at the start. I've already purchased my materials so at this point I've moved on from those original bulk numbers, feeling confident that I have enough to complete my total mix. At that time I'll be following, more accurately Al's recipe quantities.

Admittedly, I don't yet know enough to understand soil PH well, and I have to start somewhere. I'm relying largely on other's advice, so now the remaining question would be "is Al's recipe a good one". Given the number of times I've heard others reference it, I'm inclined to believe that it is. If anyone can share specifics (or information sources) on soil PH and how you are all arriving at your numbers, that would be great. The results of my research have been kind of across the board. Al's recipe calls for 4 tbsp per 1/2 gallon of peat, while Seysonn recommends 0.5 tbsp per half gallon. I've read other sources cite 8 tbsp per 1/2 gallon of peat. That's a pretty dramatic difference from all sources unless I'm entirely misunderstanding the information at hand. I'd love to understand it better if anyone has any (preferably quantifiable, not just anecdotal) info they'd like to share. I know the chemistry can get pretty complex so if we can keep tips at the kindergarden (pun intended) level, that'd be swell. :-)

Thanks everyone for the time you all take to share your thoughts!

I think you may have a typo in your message, Cliff. You would not use 1 cup of lime per gallon of bark. The formula is roughly 1 tablespoon of lime per gallon of finished mix (including the perlite and peat or whatever takes their place). I think that's closer to what you said in your original post. There are 16 tablespoons in a cup.

Just to clarify, the purpose of the dolomitic lime is two fold: to bring the pH of the mix closer to neutral and to provide calcium and magnesium, which are often missing from otherwise complete fertilizers. If you wanted to grow something in a 5-1-1 mix that prefers a very low pH, you could use gypsum to provide the calcium instead of using lime. In that case, you would need to use a fertilizer that includes magnesium.

I've been using 5-1-1 for all my vegetables and flowering annuals for five years now, and I love it. I started out trying to follow the reccipe exactly, but since then I've made modifications to fit my plants and my environment. Once I understood how a fast draining mix works, it was easy to modify it while staying close to the original intent. For example, I often use a good quality soilless mix (like Promix or MetroMix) for the peat fraction. And in my large fabric containers where I grow most of my vegetables, I've started using Napa Floor Dry (which is kind of like Turface) in place of the perlite because it helps retain more moisture.

Hi Ohiofem, Thanks for the info. I'm positive I'm overcomplicating things at this point. I need a mental reset I think...

I may have a typo above and if so, I'm sorry (I don't see it or I'd correct it). There are two different parts to my post above:

Point 1. My original post's (outdated) estimate of 1 cup of lime per cubic foot of pine. This is merely multiplying the 2 cups of lime in the 2 cu ft version of the "big batch" recipe by the 7.5 batches I thought I would need to produce. Maybe my math example above was confusing. What I meant was:

15 cu ft of pine / 2 cu ft per batch = 7.5 "Big Batch" recipes.
7.5 batches * 2 cups lime per batch = 15 cups lime total

Point 2. My understanding of 4 tbsp per half gallon of peat based on the "small batch" recipe.

Those two points weren't really intended to go together. I think it best to throw out my numbers from the original post and focus on the correct amount of lime to use per "batch" of mix.

Part of the complexity for me in trying to nail down my understanding are all the different ways to look at the materials and measurements compared to the lime. How much lime per total produced mix vs. how much lime per gallon of one specific component (e.g. peat)? How much lime per gallon of component x vs. how much lime per cubic foot of component y?

Here's the place for the mental reset:

I'm getting close to the point where I feel like over thinking it is adding a good bit more confusion than this probably should produce. Can I simplify this by mixing the lime in at 8 tbsp of lime per gallon of peat? This is based on Al's "Small batch" amount of 4 tbsp per half gallon of peat. Obviously other components would be added in proportion to the recipe:

Small batch doubled:

6 gallons pine bark
1 gallon peat
1 gallon perlite
8 tbsp lime (or gypsum in some cases)
1/2 cup CRF (if preferred)

Repeat until really big box ends up full...

Unless someone is telling me this recipe is wrong somehow, I'm thinking that just following the original directions is a safe bet at this point.

Also (I know I'm going to regret asking this but your reply mentioned it), should I specifically avoid fertilizers with CA and MG if I use this amount of lime?

Again, thank you to everyone taking the time to go through this.

I'm sorry, Cliff. I think I had a typo in my mind, and thought you were mixing up cups and tablespoons. My bad. Your last recipe sounds good. It makes 8 gallons of mix and takes 8 tablespoons of lime.

Since I use the small batch as a starting point, I aim for 1 tablespoon of lime per gallon of finished mix (not just pine bark or peat). The small batch makes 4 gallons of mix and calls for 4 tablespoons of lime. Since you want 21.5 cubic feet, or 157.5 gallons, of mix, I was using that as my starting point. 157.5 tablespoons equals just under 10 cups.

The reason I break it down to tablespoons is that I can only make about 20 gallons or so at a time. Unless you have a cement mixer, it's hard for me to imagine how you could make much more than that. I use a compost tumbler to mix my components. I make about 500 gallons of 5-1-1 each summer, so I've done a lot of mixing.

Thanks for the follow up Ohiofem. I think that confirmation puts me in business. It'll be a little more work to measure the pine by the gallon instead of 2 cu ft bags, but honestly not that much more. I'll probably make a 4 gal batch first, then an 8 gal batch, and then try 12 (if it's not too unwieldy). I plan to hijack my kids' kiddie pool to do my mixing in, so I should be able to make a pretty decent batch at a time and get it done pretty quickly. Then I'll have a few weeks to let the lime do its thing before I start planting near the end of Feb.

Thanks again!

Also (I know I'm going to regret asking this but your reply mentioned it), should I specifically avoid fertilizers with CA and MG if I use this amount of lime?
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Most time release granular (or water soluble) ferts don't have Ca. That is the reason for adding lime/gypsum. But if your fertilizer already has Ca in it, so much better. I uses MG "Shake-n-Feed" for tomatoes and peppers which has Ca and Mg.

The other thing here is that I wouldn't take this as perfect science/chemistry. The ratios 5-1-1 ( 7 Tbs + 7 Tbs ) are just guide line. Say I make it as 6-1-1. I can even use 6Tb- 6Tb. It is not going to be a major violation. Remember that this initial addition of supplements is not going to last for ever. Somtime down the road you have to supplement. JMO

Seysonn

I used a small kiddy pool and a snow shovel to prepare my first few batches, but it was hard on my back. When I decided to go whole hog, I bought a small compost tumbler that held about 25 gallons for about $100. Then I got a 5 gallon bucket and a 1 gallon bucket from the hardware store that I used for measuring components. It turned out that using the buckets was a good idea because there was a lot of variation in the actual amount of bark in a so called 2-cubic foot bag. With the buckets, I could mix 5 parts of bark in the 5 gallon bucket and 1 part each of the perlite and peat in the one gallon container and know that I got the ratio right.

Yeah, it might be a little hard on my back but I'll just get my pregnant wife to do all the mixing. That should solve that problem!

;-) (Kidding)

Soilless Substrate Management For Nursery Crops

by Dava Hayden

Extension Associate for Nursery Crops

http://www2.ca.uky.edu/HLA/Dunwell/SoillessSubstratemgt.html

Why is peat moss so important?
http://www.peatmoss.com/blog/using-peat-moss/home-gardeners-why/home-gardeners-why-is-peat-moss-so-important/