NPK is NPK. There isn't blueberry NPK or citrus NPK or rose NPK. But it's true, many people buy the name as much as the content.

Go to an independent garden center, describe your situation and ask what they recommend. One thing I know is you won't want to be using an alkaline product on the blueberries. Also fabric containers are intended to be placed within the ground.

Oh, this is long, sorry.

@gardengal48 (PNW Z8/9) here is one of the threads I am using as a basis for what I'm doing, where you and others had expanded in detail about organic container gardening: https://www.houzz.com/discussions/1527370/organic-fertilizers-for-containers

It's quite old, but has good info there.

If I am using a potting mix such as one from G&B as one of the components of the container media, I should hopefully have some microorganisms (?), together with the fertilizer from dr earth (e.g. "life", apparently is already "active") which appears to have a bunch according to the label, along with the marketing babble of humeric acid. I know I hadn't mentioned the potting soil in my original post above, I do have a bag and was considering omitting it after watching several videos put on by a local nursery - I can link to it if you are interested, it's Gary's Best Gardening, and realizing I've probably choked two citruses to death over the last year since I only used a citrus soil for them without anything else.

I stumbled on his videos after noticing quite an inventory of his branded bags at the local nurseries and researching what it was. The videos are local gardening seminars covering veges, blueberries, avocados, citrus, etc, and of course he is promoting his bagged soil product(s) which are basically mixtures of sand and peat moss, or sand, moss, perlite, charcoal. Nothing overly complex. It's all promoted for basically any kind of container gardening. He additionally seems favor the Dr Earth "life" which according to the marketing fluff is an already-processed (or in-process) fertilizer. I've also traded emails with a strawberry dude on the east coast who has grown alpine strawberries in containers, using similar media, and he has had success with the espoma branded products.

The labeling, minor changes in the mixtures, marketing fluff, etc, on the fertilizer products make the choices too confusing.. I went as far as creating a table in excel listing the products from the brands, writing down ingredients were possible, along with any numbers. The Dr. Earth stuff is all so similar to itself, while the espoma stuff is all similar to itself as well. So... errr... well, anyway. I think I'm just using this here to express frustrations :p

In case anyone's concerned, the diy landscape bags are going inside plastic buckets that are cut-up/drilled to allow for the aeration. I went this route because I couldn't get any of the bags to correctly fit, and, well, this was way cheaper, too. I'm going to either tap them into my drip system or place them atop smaller containers for SIP-style, TBD.. if you all have suggestions on this, I'm open to hearing it :) The strawberries and blueberries are already in this diy sip setup, happy to share photos, but privately.

The blueberries are in a media mixture of kind of equal G&A acidic mix, peat, fir bark, perlite, worm castings. Two of the three blueberries were potted in December, and I scratched some feather meal into the their soil last week. The strawberries have been grown from seed, and potted last week in a similar mix as blueberries except coir instead of peat. I spread a little feathermeal about 2/3-up into the container when I prepared it.

weeeee

J - Fertilizer producing companies advertising and packaging have most hobby growers believing they need a variety of fertilizers to cover the nutritional needs of each different plant. While it's true that some plants have somewhat unique nutritional needs, the fact is, more than 95% of the plants you're likely to grow will do very well with one fertilizer.

If fertilizer was plant food, it could be said that plants eat salts, which dissolve in water to form ionic compounds, which in turn are absorbed by roots and carried to all viable plant tissues in the nutrient stream. Plants do not care whether their nutrition comes from dead plant matter, a rotting fish, the various meals (hoof/ horn/ bone/ feather/ blood/ alfalfa .........., or from a container of liquid synthetic fertilizer, like Foliage-Pro 9-3-6, which is what I and many here use to the exclusion of all or almost all others. I'll leave a link to something I wrote about fertilizing plants in containers, followed by something else I wrote about nutritional supplementation.

Click me and I'll take you to more info.

Some Perspective re Synthetic:Organic Nutrient Supplementation

tapla

I'm
going to approach this issue by looking at it from a growth
perspective. IOW, what will make my plants grow best, and what will
ensure that they are able to grow as near to their genetic potential as
possible. Politics and ideologies aside, I'm hoping that the reasoning
will be viewed as sound. This is about gardens and beds ..... not
agribiz.

In my gardens and beds, I adhere pretty strictly to the idea that on
an ongoing basis we should use organic products/soil amendments that
build the soil structure to minimize the need for soluble (read
synthetic) fertilizers and nutrient supplements. That said, there are
times we need individual nutrients to complete the assortment of
essential nutrients plants take from the soil. If you're limited by a
rigid 'no chemicals' ideology, you either deal with the abnormal/sub-par
growth associated with deficiency ..... or wait, while you hope the
organic matter you've added eventually solves all the issues. If, on the
other hand, you are NOT limited by rigid ideology, the issue is easily
solved with a soil test and the addition of the appropriate nutrient(s)
via a chemical compound like potash, various nitrates, phosphates, etc.

There are extremists at both ends of the organic vs. chemical
approach to gardening. Some never think about the soil, believing it
just fine to depend on the continual addition of chemicals to
'hopefully' produce growth. Others would never even THINK of using a
chemical, and will chastise anyone who does. When it comes to my gardens
and beds, I'm in the middle, but as noted I do lean quite heavily
toward the organic side, though I stop short of telling anyone what they
must do to be a good gardener.

Briefly: where container culture is the topic, soluble synthetic
fertilizers get the nod from me - hands down. They are easier to use; we
know exactly what nutrients our plants are getting and when they are
getting them; delivery of nutrients does not depend on the activity of
soil organisms whose populations vary in boom/bust cycles in containers;
you're using a soluble product, not an organic soil amendment that has
the potential to clog valuable macro-pores; you need not worry about
soil structure, because if you are smart you will have built it into the
medium before you planted in it ...., but let us save the container
soil topic for another day.

I mentioned there are those at one end of the spectrum who would
never lift a finger to improve their soil. Adding organic matter to
their soils would be as foreign to them as adding exercise to life's
itinerary. On the other end, are those who stand ululating and
hand-flapping (credit to Dan for that one) at the very thought of anyone
using Miracle-Gro. From the plant's perspective, both extremes are
ridiculous, and from my perspective, both extremes are unnecessarily
self-limiting. The plant just wants to grow to its genetic potential. To
do that, it needs a soil that supplies the right amounts of air and
water (good structure), and a full compliment of the nutrients plants
take from the soil, and it doesn't care if they come from compost or
Miracle-Gro.

Perhaps a more logical approach to plant nutrition might be to look
at soluble synthetic fertilizers in the same way we look at IPM
practices. Use the most naturally harmonious method/product we can to
ensure plant growth or yields are in what we determine to be the
acceptable range. I realize that in most cases, we can do this by adding
more OM, but not always. Often too, time is a consideration. We may
have someone who wants to plant immediately, in soil that is deficient
in one or more nutrients. We probably shouldn't expect someone to forgo
their own freedom of choice and wait two years or more while the soil is
fortified/improved only via the addition of organic matter, just so
they don't have to suffer the wrath of someone who might not think them
'green' enough to join their club.

There is a technical difference between a fertilizer (Miracle-Gro)
and a soil amendment (feather meal), but even that point eventually
becomes moot from a strictly nutritional perspective. Plants take up
elements that are dissolved in the soil solution and in ionic form. What
they take up are salts. The large molecules that make up hydrocarbon
chains in organic fertilizers/soil amendments cannot be taken up by the
plant unless the hydrocarbon chains are broken down into elemental,
soluble form by soil organisms. At that point, the elements from soluble
fertilizers are the same as the elements from organic sources, which is
why the plant could care less. At the point in time where nutrients are
assimilated, they are ALL soluble and in elemental form, regardless if
they came from a dead fish, compost or a hose-end sprayer.

If we could only achieve happy healthy plants in a soil teaming with
life, using only organic soil amendments and fertilizers, how do we
explain hydroponics? ... no medium, or an entirely inorganic one, and
only soluble sources of nutrients. At the very least, hydroponics
suggests there is a middle ground in which everyone can seek their
comfort level.

For more than 20 years, I have been growing perfectly healthy plants
in containers, using a medium whose only organic fraction is 1/3 or less
pine or fir bark; the rest of the ingredients are large mineral
particles like Turface and crushed granite. I have used ONLY soluble
fertilizers in these soils, with the hundreds of pictures I have posted
here at GW serving as concrete proof that happy, healthy plants can
indeed be grown using only synthetic soluble fertilizers, if the soil
structure is favorable, which leads me to the reason for writing this:

Colloquially, the term 'organic' formerly applied to things once
living, but even some plastics contain carbon and are considered organic
compounds as well. It really is misleading when we throw the word
around w/o much consideration, but I admit to being guilty of it from
time to time as well. Technically, urea, ureaformaldehyde, isobutylidene
diurea, and crotonylidene diurea (forgive me if the spelling is
slightly off) are all organic molecules, and actually do an extremely
good job of feeding microbes, which strongly reinforces the idea that
synthetic fertilizers are getting framed for the microbial murder rap
that should be hung on the effects of reduced OM in the soils. The
microbial murder rap should be hung on the effects of reduced OM in the
soils; purposely redundant so it could not be missed.

It's a vicious circle - mineral soils can support optimal plant
growth (nutritionally speaking) only if enough young decaying matter is
returned to the soil regularly and frequently. Prairies and forests are
virtually self sustaining because all vegetative matter is recycled back
into the soil. If we regularly mow and bale the grassland, or log off
the forest, nutritional deficiencies are assured as a result of our
removal of the OM that would have provided future nutrition - thus the
tendency/need for us to adhere to the practice of replacing the lost
nutrients using chemicals. Perhaps I should put that another way - ....
replacing the deficient nutrients using chemicals.

To be clear, this isn't a 'What came first, the chicken or the egg'
thing (it was the egg first); it isn't the fertilizer chemicals that causes the ravishment of
the soil, it is the ravishment of the soil that is causal of the
necessity/tendency to use the chemicals, particularly where expedience
is key.

In our gardens/beds/lawns ..., we can add compost or other OM to
replace the vegetative matter we remove and use or discard. For more
than 20 years, I've used compost regularly in the gardens/beds, and
applied fine pine bark mulch 2-3" thick, usually every other year. I
have extremely healthy soil and rarely find it necessary to use anything
synthetic.

You can find opinions all over the net that chemical fertilizers are
laying waste to the landscape, and wiping out microbial populations
faster than chocolate disappears from the candy dish in the family room.
Are these opinions based on political views and a radical ideology, or
warranted and based in fact?

In research by Texas A&M University, intensely managed (read
'managed using chemical fertilizers') sports fields with mostly a sand
substrate showed no shortage of soil life. That is there were 10s of
millions of bacteria, and 10s to 100s of thousands of fungi per cubic
centimeter present in the heavily managed soils. Part of the study
included measuring soil life in 11 inches (deep) of pure sand that
contained no additional organic amendments whatsoever, over which washed
sod was placed. As the sod 'grew in', soil life populations increased
almost immediately, 10-100 times their previous numbers.

Soil life populations just sort of hang loose, waiting for something
they can digest. If they don't get it, they die and feed off each other.
When organic matter is introduced into the soil, they break it down,
and their numbers increase. When they've consumed the organic matter,
they die and consume each other, but the base population remains, ready
to spring into action the moment more organic matter becomes available.

What do soluble fertilizers do? They make plants grow. Sure,
extremely high concentrations of chemical fertilizer poured on the soil
in volume might kill some microbes in the immediate area, but the o/a
affect of chemical fertilizers is actually an increase in microbial
populations through increased plant growth/mass. You need only look to
the fact that the rhizosphere (root zone) of plants is such a popular
gathering place for soil biota to see increased plant mass promotes a
marked increase in soil life. It's actually the continual 'taking' of OM
from gardens, agricultural fields, lawns ... w/o replacing it that
reduces or inhibits the communal activity of microbial populations; even
then, they are ever ready to bounce back ... if you just give them
something to eat.

None of this addresses the hot button political, ideological issues
too many wish to export from their own value set, other than the fact it
points out the folly in occupying the margin's extremes. Again, I'm
pretty pragmatic and results-oriented, so I tend to approach this
subject from a plant/soil/growth perspective and leave the politics to
the ideologues. My personal view is that in the o/a picture, a chemical
fertilizer or nutrient supplement judiciously and responsibly applied to
our gardens when it's found to be needed isn't the earth's end; and I
prefer to use my own sense of right/wrong to set my course, rather than
be told what I need to do to be a good, responsible student of
husbandry.

That said, avoidance of unnecessary chemicals in the gardens/beds to
the greatest degree I feel is reasonable, is still my normal MO. YMMV,
but options are good, and I prefer to keep mine open.

Al

That's interesting about nitrates and blueberries. I didn't know that. I have used ammonium nitrate on blueberries, with no obvious ill-effect, but maybe I should have been more careful.

I wouldn't worry too much about fertilizer pH. You don't use enough of it to change the soil pH significantly.

Actually, much of the info in that previous thread is not so good at all.......including my initial post :-) It's amazing how much more educated and well-informed one can be with going on 12 years of additional container gardening research and experience!!

Whatever potting soil you use is not gonna make any difference. There simply will not be the populations of soil organisms necessary to efficiently process ANY organic fertilizer. Whatever microbes that may be included in something like the G&B soil or the Dr. Earth ferts tend to be limited to mycorrhizal bacteria which are helpful but will not begin to address the efficient conversion of an organic fert into a plant usable form.

The long and short of it is if you want to be organic, grow in the ground. If you want to grow successfully in containers for any more than a single growing season, stick to synthetic fertilizers.

I'll be using home-sewn fabric pots (using landscape fabric)

Fabric containers as in those used to produce field grown nursery stock were developed strictly for in ground use, are not intended to be left on the plant after digging for final sale - let alone as a solid walled container equivalent that is out of the ground the entire time the plant is in it. With the purpose of using the fabric being that the plants will be able to produce these sort of half roots that grow through the fabric into the soil, enabling them to enjoy benefits of growing in the ground. Yet can still be dug up later, without the same degree of root loss as if they were growing completely without confinement.

But maybe you are actually talking about a different kind of fabric. Although I would still wonder how well anything called fabric would work as an above ground plant container - why that would be used instead of something more conventional.

@Embothrium: Sorry if my terminology is incorrect. By "fabric" i mean the woven plastic you find on landscape fabric/cloth/cover. Examples of such commercially available items include grow pots, smart pots, rain science grow bags, etc. None of these fit my buckets well, so I decided to make my own.

Thanks for sharing updated knowledge, @gardengal48 (PNW Z8/9). Sadly, the area where I have ground available is nearly full shade, so, I won't have success with edibles (unless it's something like wasabi but there's only so much of that I could eat hahahah). I will consider non-organic container fertilizer, but maybe this is one of those things I'll have to learn on my own :p

This actually begs the question.. can I just mix in some ground dirt into my mix now that I'm adding things to help with aeration?

What about raised beds? There's an area I'll be able to access in a year or two once the HOA replaces our fences, and I plan to turn that into a raised bed.

" This actually begs the question.. can I just mix in some ground dirt into my mix now that I'm adding things to help with aeration? "

Not if you want to grow any plants successfully long term - longer than a single growing season - in any kind of container. Read Al's (tapla's) post carefully as well as those he linked to for a better understand of why you cannot substitute inground amendments or growing practices for container gardening. Two completely different methodologies involved here!!

Raised beds (without a base) are just the same as growing in the ground and the criteria that apples to containers does not apply here.

And do not be concerned about fabric grow bags being used above ground :-) They are sold at every nursery and garden center specifically with that in mind - for potatoes, tomatoes, strawberries, etc. - and in a wide range of sizes. They are not the same as the fabric root pots/bags used for landscape stock that Embothrium was referring to.

For some strange unknown reason I missed the super long post by @tapla (mid-Michigan, USDA z5b-6a) (Al) and now just had a chance to read it.

I have no problems with growing hydroponic edibles, in fact, I actually prefer it, and would do that on my patio/balcony and garden area here if it weren't so complex to setup in a way that's acceptable to me*. My preference is because it's much easier to measure the numbers and know what's going on, and also... it pretty much eliminates the whole "am I watering too little or too much" conundrum hahaha.. :) That's partly why I'm sort of leaning towards the DIY SIP containers, versus the drip irrigation. The way I resolved the "chemicals" issue in my head, was that the application of the food was nothing more than salts, as Al wrote above. Same way I got over MSG.. it's all just salt in a manner of speaking.

* We setup DWC hydroponic tomatoes at my moms house a few years back for various reasons. It ended up being too complex for her, as she never grasped the "numbers", so I just visited every other weekend and tended to them myself. Sadly, the rats got to them before we could enjoy any crop (one tomato only, it was tasty, and ginormous). Four issues with the setup: startup cost, did not look nice, pumps were noisy, and continued cost (electricity here is stupid expensive). All of these can be solved (patience, better planning, pump enclosure, and bulk purchase of chemicals and install solar.. all respectively) but kindly let's leave that out of scope for this discussion :)

Since I have no issues with hydroponics, I suppose I should have no issue using chemical fertilizers. The issue only comes up if I share my food with others, can't boast "organically grown". Hmmm. Nasty nasty chemicals :P

I will read up on the non-organic fertilizers, remain open ended, and try to find the least of all evils.

All that said.. what sort of feeding would be needed for container-grown ramps? I've read it couldn't be done in my zone, but.. but... I've got ramps sprouting in my DIY containers. Muwahahaha! Hopefully I can get them to last more than one season, and begin to multiply.

Thanks all again for your time. Interesting discussion.

rather than post misinformation about organic gardening, i will make this short 'n sweet and factual.

there are primarily two types of kind of organic fertilizers, choose one depending on the type of way you'll be gardening.. Organic fertilizer can in fact be used in pots. it all boils down to one thing: water soluble or insoluble.

next to the ingredient list, you will see whether it is primary water soluble or not. water soluble means that mixing it with water will feed the plants instantly. insoluble means it must be broken down by decomposition (typically this is a fertilizer you would use when planting in the ground).

for organic fertilizers you can use something like a fish emulsion (preferable a fish hydrolysate) or something like Miracle grow organic which works well in containers due to it being water soluble (7% of it's 9% nitrogen is water-soluble).

@stevie groovie. This actually works well for me, as I have a kelp/fish fertilizer that I've been using diluted, as well as spraying my pineapples. I'll give this a go with the vegetables since they are annual, anyway, and easy to refresh the dirt in the containers. The citrus will take some more research before I accept good news like this, since I'd like those to be mostly permanent :) Thanks for more ideas to read about!