Miracle Grow Garden Soil - problem?

Thanks

Ok. I'm just about ready to make
Something happen here. The soil was bone dry this morning, so I leveled and watered for 15 minutes.

Tapla, much later today (8 hours) I dug a hole to bury some scraps and the soil had dried out again. What do I need to add? The shop absorbent w/o DE so I don't hurt any worms? There are no worms in the bed so far.

Here's a close up.

It looks like a LOT pf organic material & not much topsoil or fine sand. What did you mix together to come up with your soil?

Al

T,
I mixed up EVERYTHING I ever grew anything in! Which includes the following:
Miracle Grow Potting Mix
Black Kow Composted Manure
Bocabob's Coco Coir
A commercially purchased Rose garden blend
My homemade compost
(comprised of layered shredder paper, coffee grinds, veggie peels,
and leaves)
Some leaf mold

Uh, now that I review the list, it does look rather "organic," huh?

So, even though a shovelful seems to be pretty "sandy," there's not enough "umph" to hold the water? Please send recommendation.

Thanks!

Linda

I would add some fine Turface (finer than Turface MVP) and/or some fine play sand, making sure the sand wasn't salty. Native topsoil, if it's not too coarse, would also work well. Original recommendation was at least 50% mineral fraction. ;o)

Al

OK I really need to read this thread from the beginning, thanks Linda for pointing me to it.

Thanks, Al!

Carminator1 seems to have the exact opposite problem as I have with her growing medium. She's got mineral fraction, but wants to add unfinished compost. I told her to read this discussion, paying attention to "shrinkage" due to unfinished compost breaking down...

Linda

..... and nitrogen immobilization, not to mention the additional heat generated by the composting process.

Al

Yes thank you for telling me, I thought I could get away with it since the only things left to decompose was just brown leaves and sticks, the rest seems to be almost done.

Tapla,
Looks like I'm going to be back to strictly CONTAINER gardening after all, this season, since my transitional move has transitioned once again. I won't be planting in that big raised bed after all.

Here's my NEW question regarding container soils. I've usually grown my brassicas in my homemade eBuckets, and my collards and mustard greens in my patented Earthboxes (like the SWCs). The base medium has always been MG potting MIX (no soil in containers -- got it!). At first, I started off with 100% MG potting mix. Then, when I learned brassicas love organic mediums, I started mixing in 50% MG Potting mix, 25% homemade compost, 25% Black Kow composted manure. I got great results until I inadvertently introduced that garden blend SOIL into the "mix" and it started compacting hard as cement. I'll be starting over COMPLETELY, since everything's been dumped into that one raised bed.

QUESTION #1
How would you proceed for building a planting medium for organic loving brassicas growing in 5-gallon self watering eBuckets?

Also, I might as well just direct sow (DS) my brassica seeds into my eBuckets right off the bat. But, I've always used commercial seedlings and have never DSed anything before.

QUESTION #2
Will the planting medium you recommend in question #1 accommodate direct sowing the seeds in that medium?

Thanks!

Linda

1) You don't get as much compaction in SWCs when you use peat-based soils as you do in conventional containers watered from the top. The key to best success is having a soil that wicks adequately w/o getting too soggy. Since you asked me how I would proceed, I can tell you that I would probably start with a mix of 5 parts partially composted pine bark fines, and add 3-4 parts of peat, and 1 part of perlite, along with 1/2 cup of dolomitic lime/cu ft of soil. How much peat I added in relation to the bark fraction would depend on how fine the bark is, and how many fines it contains. The first couple of times you made the soil, it would be largely trial & error - adding a little more peat to the mix until you think the wicking is right. Subsequent batches would be more by 'feel' - like my mom made bread - no recipe - all 'feel'.

Alternately, you could just use your potting soil as the peat fraction & reduce the lime by half.

If you get the wicking right, it's likely all you might need to do is mist the top of the damp soil until the seeds germinate.

Al

So, I could go ahead with the MG potting mix is what you meant as "alternately?" I'm not sure I'll have time to experiment with the wicking, and I've never worked with peat before...

If I go with the MG potting mix again, do I need to add anything for an organic component? I do still have my bin of partially finished homemade compost..

What I meant was you could use the 5 parts of bark along with 3-4 parts of potting soil and a little perlite & lime, but do whatever you're comfortable with. I think the more highly aerated soil would yield better results, but it depends on what kind of effort you're willing to put into it. Lol - though that's kind of a silly statement - based on the enthusiasm & ambition you've already demonstrated. ;o)

Al

(No "rain in Spain, is falling mainly in the plain," yet, as Eliza Doolittle still may not have it right...)

So, by potting SOIL you mean some of what I threw into that raised bed?

5 parts Pine Bark Mulch / Soil Conditioner
3-4 parts of my Veggie Garden Soil / Peat (adjusted for wick-"ness")
1 part Perlite
Dolomitic Lime

??,Professor Higgins?? ^^_^^

That sounds right to me but I am far from a soil expert.

"rain in Spain, is falling mainly in the plain" and the rain in Moroco hit you mainly in the coco (head) sorry I could not help myself.

When I mentioned "your potting soil", I was referring to the MG potting mix you had referred to:
5 parts of partially composted pine bark (or bark that is uncomposted, but in small pieces - like in the picture below
3-4 parts of peat or the MG potting soil
1 part perlite
1/4 cup dolomitic lime/cu ft of soil if you use the MG - 1/2 cup/ cu ft if you use peat

Al

The bark at 3, 6, and 9 are ok, but a little finer would be better for SWCs.

I just want to say that I have never gotten so confused as I have reading Gymgirl and Tapla. It seems they are tracking each other ok but I just can't remember what was said ten posts above the one I happen to be reading at the time. It is just my brain doesn't work like that - I am a very serial person (engineer) and Gymgirl seems to be the epitome of the multiprocessor type. Despite all that, I have to say that this has been a real HOOT and I have thoroughly enjoyed it!

I think I am just going to grow my fig trees in a mix of fine wood, worm pile castings and sandy soil. As Tapla said long ago and far away (above) figs are genetically very tolerant.

Ah yes - Figs ARE genetically very vigorous, but Liebig's Law still applies. There are 6 factors that affect plant growth and yield; they are: air, water, light, temperature, soil/media, and nutrients. Liebig's Law of Limiting Factors states the most deficient factor limits plant growth and increasing the supply of non-limiting factors will not increase plant growth. Only by increasing the most deficient factor will the plant growth increase. There is also an optimum combination of the factors and increasing them, individually or in various combinations, can lead to toxicity for the plant.

Because figs are vigorous, they will tolerate growing conditions (to a degree) that other plants might be unable to tolerate ..... but that doesn't mean that less than ideal conditions will see them growing to their potential, or humming along at the level of vitality they are capable of.

It is actually a plant’s vitality that we can hold sway over, not its vigor. ’Vigor’ is constant. Mother Nature provides every plant its own, predetermined level of vigor by building it into the individual plant. Vigor is the genetic potential every plant is encoded with, and its measure is the plant's ability to resist stress and strain. Vitality, in contrast, is variable - a dynamic condition that is the measure of a plant's ability to cope with the hand it's dealt, culturally speaking. A good way to look at the difference between vigor and vitality is to look to genetics for the level of vigor and to things cultural for the plant’s vitality. It's up to us to provide the cultural conditions that will ensure our plants' vitality. Vigor and vitality are distinctly different, and a good case could be made that they are unrelated, but there is no need to delve deeper into that point. A plant can be very vigorous and still be dying because of poor vitality. Far more often than not the term 'vigor' or 'vigorous' is misapplied, where in their stead the terms 'vital' or 'vitality' would have been more appropriate. Poor vitality is what we witness when our plants are growing under stress or strain and in decline.

Please take my offering more as from the pedant than the preacher. ;o)

Al

This thread is a little aged but hopefully someone might respond (ideally Tapla or Gymgirl). I have been reading some of the many, many threads about soil in containers and have learned A LOT!! I completely see the reason for a gritty mix and will be searching for some pine bark here pretty soon for a potted hydrangea. (Sidenote: I know it's a gamble to have a hydrangea in a pot, but it is a large pot, and I'm willing to try)

My question/concern is that in the Dallas Metroplex we get similar heat that Gymgirl gets in Houston, just much much drier. It is no surprise not to get rain for a month or so during the summer. So with this super efficient, fast draining soil...wouldn't it dry out much faster? Unfortunately, I can't tend to my plant all day because nobody pays me for that, so what kind of watering schedule are we looking at for 95-105 degree weather?

Thanks for all the info so far!!!

HC

HC, thanks for revitalizing this thread. I am not sure what your question is here but your post made me think of something new about using wood chips. I had planned to line the bottoms of my raised beds with cardboard, then several or six inches of wood chips (Western Red Cedar) this year based on some information I have been reading about here. I have an electric McCollock grinder which could be used to pulverize these same wood chips to be used in container mixes as well in my outdoor manure vermicompost bins. After toying with this idea of pulverizing these wood chips I have come back to this forum to come up with some ideas on percentage mixtures for various potting mixes. Hopefully your reposting here HC will stimulate some more information in this fascinating posting.

FMS - ultimately you have control over the water retention in your soil if you make your own. By choosing finer bark or increasing the peat, you can gain a LOT of additional water retention, but what weighs in the balance is plant growth/vitality. Your plants will undoubtedly have a much better opportunity to grow to their potential in a soil that requires watering daily, but not everyone is willing to be inconvenienced, so many are willing to trade a little potential for the convenience of watering every 2-3 days instead of every day. Personally, I have to make the watering circuit daily anyway, so it matters little if I have to water 200 or 300 containers - 20 minutes. I'm all about working toward maximizing vitality - the rest just seems to fall into place when I remain focused on the plant's health. Everyone is different, with a different set of priorities, so EMMV.

MR - I'd like to try to answer your question(s), but I'm unsure what you're asking?

Al

Hey T,
I am enjoying working with your 5:1:1 (in my case, 3:1:1) container mix as much as Bocabob's coir! It is sooooo clean on the hands!

And, I am totally stoked over how much the MG potting mix is stretching! To date, I've potted up five 5-gallon eBuckets, two 6-gallon containers, and Five 10-gallon containers, and I still have 1/4 of a 2.65 cu ft bag of MG potting mix left. Have used less than 1/2 bag of perlite, too.

QUESTION: How often should I fertIlize with the water soluble MG 24-8-16?

Hugs!

Linda

Hi.

I've tried to read this thread as it pertains to raised beds, though I'm not sure I understood it all.

I have a question for Tapla or anyone else with advice:

I'm building three raised beds this spring, for the purpose of growing vegetables and herbs.

Today, I visited a local nursery to get some pricing on soils. They do sell a mixture of top soil, compost and bark. But they seemed to think that mixture was only for use in beds for flowering plants and bushes.

And that for a veggie raised bed, I would just want the top soil and compost.

Does that sound right?

Sarah

I can't think of a reason you can't use the same soil for flowerbeds as you use for veg garden, unless they are thinking it's too coarse for good planting from seed --- vegetable gardening might be thought of as more 'seeding' and flower bed as 'planting from potted plants'

Seran72,
When I build my raised beds for the fall, I'll be using Tapla's rationale of a mixture containing topsoil & pine bark, and maybe some sand.

I've learned from him that a well-aerated, well-draining planting medium must contain a non-organic component to it that will not break down or collapse/compress. That's basically what the inorganics in his recipe does -- provides "structure" to the medium. The "chunky" stuff creates air pockets.

Then, he adds all the organic amendments the law allows, for factors like nutrients and a playground for the good soil life, and earthworms, etc.

Finally, he fertilizes on a very regular basis.

It a minute or so, he'll come along and either confirm or correct what I've tried to convey above...

Linda, Al's PBF (pine bark friend) forever! ^^_^^

Hi, All -

I've actually read this thread through again for approximately the third time. :-) It's all starting to sink in and I just can't thank everyone enough, and especially Al, for taking this kind of time to share knowledge.

I am definitely going to be ordering the three part mix (topsoil, compost and pine bark) from the nursery for at least part of the mixture.

I am planning one or two no-dig beds that are four feet across, perhaps 8 feet long and will be 20 inches deep. I'm laying cardboard and wet newspapers at the bottom, then some chicken wire to keep the voles out.

My remaining questions are this:

1. I think I am understanding that sand and Turface (and topsoil) serve the same purpose, which is as a mineral component to prevent breakdown into too fine of pieces. And that I want the mineral component to be 50%. Is that accurate?

If so, I already have some sand, there is 1/3 topsoil in the 3-part mix I am going to order from the nursery and I will get the remainder (to reach a fraction of 50% mineral component) from some Turface.

2. Should I add some lime to the mix?

3. Because my beds are 20 inches deep, this is all going to get somewhat expensive. Are there any downsides to layering some browns (straw or dried leaves) and greens (fresh grass, coffee grounds, kitchen scraps) at the bottom of the bed so I don't have to put so much soil in?

If I do this, I will mix in sand/turface in those layers to maintain the mineral component??

If this is okay, do you have any advice on how many inches of that I can do before I need to start my official soil mixture (the three part bark/topsoil/compost mix from the nursery plus sand/turface to reach a mineral component of 50%).

Again, thank you so much for the advice.

Sarah

Lol - Thanks, Linda.

Water behaves differently in the ground than it does in containers, and for all intents and purposes it behaves pretty much the same way in a raised bed as it does in a garden, the only significant difference being that in a raised bed the water pushing down from the top can cause excess water to easily move laterally across the surface of the soil the bed is built ON - especially if the reason for the raised bed was a hard clay soil.

You can grow in raised beds with soils like Miracle-Gro and similar ..... if you WANT to, but since the earth acts like a giant wick and literally sucks the moisture from them, you will usually have trouble keeping peaty soils hydrated. In the same vein, soils that are predominantly organic components (compost, pine bark, peat, etc) pretty much behave in the same way - hard to keep hydrated.

You can see the soil I have in my raised beds below. It's a wonderfully healthy soil made mostly of Pine bark fines that have composted in place, + some reed/sedge peat + some sand and some Turface. You could toss in a little composted manure too, if you can find a decent product.

Critiquing my own soil, even though stuff grows like crazzy in it and it's full of the denizens that always inhabit healthy soils, and I can plunge my hand into it around 10" easily, it shrinks too quickly and I need to water too often. I should have bulked up on a larger mineral fraction instead of it being mostly organic. More sand, topsoil, Turface fines ..... all would have offered the same excellent growth. I've been fixing that as I go by adding the old soil from my gritty mix repots, which has a lot of Turface and crushed granite in it - permanent structure in these ingredients.

So - I would suggest a raised bed soil would be about 70-80% mineral components as the structural base - topsoil, sand, fine Turface ...... and 20-30% other organic ingredients to make up the rest. It won't matter much what the organic ingredients ARE, because at that low % they won't affect the structure much as it relates to drainage. I think that finished compost or pine bark fines are an excellent addition because neither will significantly immobilize nitrogen (even if it does, that's fixable). Reed/sedge peat is another good choice.

Questions?

Al

Al,

I think our posts crossed each other.:-)

I see now that you recommend an even higher percentage of mineral component than I first thought, and I will modify my plan accordingly.

I think I'm tracking you now.

Sarah

P.s. Thank you to GymGirl as well for the info!

We were typing at the same time - but you're better on the keyboard so pulled ahead. ;o)

1) Yes - you understand that part. Just remember that the larger the organic fraction, the more and faster the shrinkage of the volume of soil in the beds. 50% mineral should probably be considered the upper limit - unless you are planting only annual plantings and are ok with lots of shrinkage - then you can use a higher % of OM..

2) If you're buying premixed soil, ask if it's limed or if it needs it. Hopefully, the soil maker will have some sort of idea about the Ca content of the mineral fraction he used. If he doesn't, lightly lime with dolomite - maybe 3 lbs/yd.

3) The only downside to adding ingredients that will break down quickly is the N immobilization (ties up nitrogen) and shrinkage will be increased as it gasses out. I probably would mix the same soil you'll use on top of it into the OM. It will all disappear within a year or two anyway, and whatever soil was above it will move down to occupy its spacial position. Plus, soil inhabitants will do the incorporation of most of it anyway. You can sort of add as much OM at the bottom as you want, but you don't want to add so much it putrefies into a slimy mess that blocks drainage & starts to ferment, producing abundant methane, sulfurous gasses, and lots of CO2.

Keep in mind that the more OM you start with in your soil, the more you'll need to add on a yearly basis to maintain the volume. And if you start with an all mineral soil and start adding OM, say 10% at a time, the graft of the quality of the soil will rise sharply to about 20-25%, then sort of flat-line. IOW, you're not going to get much bang for your buck by adding much more than 25% OM to your mineral fraction.

Al

Hey, Al,
I'm only growing veggies in my raised beds. At some point, I'd like to introduce some flowers into my veggie beds, but for now, it's all veggies in the raised beds I will be constructing for the fall (this discussion is invaluable to me, since I'm starting from scratch.)

I know the organics in the soil attract "the denizens that always inhabit healthy soils". So, ideally, how much organic component should be added to "refresh" the raised beds every season? And, If the structure is stable, wouldn't just fertilizing the raised beds with the 3-1-2 be enough for the veggies?

Do you have a per part "recipe" for raised beds?

Mineral Component