Liquid fertilizer confusion

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Perhaps I'm making this more complicated than I need to, but one aspect of using liquid fertilizers has never made sense to me.
There's lots of information out there about frequency or strength of liquid fertilizer to use, but I've seen almost nothing about the amount.

Let's say you dilute concentrated fertilizer in a gallon or two of water.
In a granular, inorganic soil like APL the vast majority of this water will drain out.

How much of this is the plant actually getting? Are you using just enough to saturate the soil as you would with normal watering? Do you use this prepared solution for several watering sessions until the can is empty and you resume normal watering?
 
How much of this is the plant actually getting? Are you using just enough to saturate the soil as you would with normal watering? Do you use this prepared solution for several watering sessions until the can is empty and you resume normal watering?

Yes.
 
Perhaps I'm making this more complicated than I need to, but one aspect of using liquid fertilizers has never made sense to me.
There's lots of information out there about frequency or strength of liquid fertilizer to use, but I've seen almost nothing about the amount.

Let's say you dilute concentrated fertilizer in a gallon or two of water.
In a granular, inorganic soil like APL the vast majority of this water will drain out.

How much of this is the plant actually getting? Are you using just enough to saturate the soil as you would with normal watering? Do you use this prepared solution for several watering sessions until the can is empty and you resume normal watering?
This depends on the soil you’re using. Look up cation exchange. Porous particles hold water and the fertilizer suspended in it.
 
This depends on the soil you’re using. Look up cation exchange. Porous particles hold water and the fertilizer suspended in it.
I understand that; that's not really what I'm asking. My question was a little sloppy and I should have phrased it differently.

Is a single watering sufficient for a "feeding"? Once you saturate porous soil with that fert. soln., you're not going to deliver any more fertilizer into the roots until it is consumed by the plant. Do you consider this one watering a "feed" and resume normal watering after? Or do you use this fertilizer solution for all waterings until you've emptied your can and resume normal watering a day or two later?
 
I always water throughly with straight water first, then apply a liquid fertilizers just to push out a little of the water I just applied. This protects the roots from salt damage if the media is dry and reduces fertilizer waste.

I make up a 30 gal solution and use a submersible pump to deliver the fertilizer.

I make my own fertilizer from a couple of bags, something like Jack's Part A and B.

Fertilizer strength is best measured by using an EC probe/meter. You need to be sure you mixed it right and your source water has not changed seasonally which mine does.
 
I usually apply liquid fertilizer immediately after watering and I know that the soil is saturated. I’ll apply the liquid feed until I see drainage from the pot. Rinse and repeat every 7-10 days throughout the growing season depending on the needs of the individual tree.

For what it’s worth, much of the fertilizer will end up being flushed away with the next watering if you’re using an inorganic soil mix. That’s why I consider it important to fertilize frequently.
 
Fertilizer strength is best measured by using an EC probe/meter. You need to be sure you mixed it right and your source water has not changed seasonally which mine does.

This. You give it a certain concentration that can generally be measured using EC. Unless it contains a lot of urea.
 
I see it as 'the concentration I'm dosing is osmotically perfect for my plant'. Meaning that this water, when taken up, will provide one dose of nutrient rich water to my plant.
Some nutrients will stick in the soil, and if the soil dries these nutrients stay behind. This can cause a buildup in some cases, especially in warmer weather.
Then comes the next plain watering cycle.
When I water again, I dilute the dose to 50%.
When I water again, I dilute the dose to 25%.
Even at 25% there's still nutrients present.
That is.. If we assume we don't flush the soil.

So I try not to water too often with nutrient rich water. Better even, is to not use liquid nutrients at all because of the huge amount of waste bonsai watering produces if we don't catch and reuse the runoff. Because we flush the soil, so we might wash out more and dilute it even further. To have the right osmotic nutrient content, we would need to provide nutrient rich water almost every second watering.
With the organic nutrients I give, if they're dry they don't release a lot. They mostly start wetting and releasing when I'm done watering, which is a super high dose locally that spreads out evenly over time. But it flushes out less, and that makes it way cheaper.

Bonsai should not be mistaken with hydroponics, unless you're doing hydroponics.
 
Maybe I’m oversimplifying, but I use liquid fert about once a week in the growing season and just mix it per instructions. Concentration is concentration regardless of amount used. Whatever the soil can’t hold will just run out leaving water with the fert concentration I mixed. I tend to have some osmocote in The soil as well so there’s always nutrients available even when the liquid fert is washed out. I feel that liquid fert gives me a little more control (maybe, maybe not) but it definitely smells better than manure and fish juice (especially indoors).
 
This. You give it a certain concentration that can generally be measured using EC. Unless it contains a lot of urea.
Absolutely true about urea, seems to have no impact on EC.
Urea is not something I use, though the landscape nursery uses it because its "inexpensive".
 
If you search this site for fertilizing, you'll find multiple threads with hundreds of different solutions to the problem. Some are incredibly simple. Some are incredibly complex. And yet, most of these people manage to grow healthy trees. I keep it simple, but if you have the time and inclination to fuss over every detail, have fun with it.
 
I see it as 'the concentration I'm dosing is osmotically perfect for my plant'. Meaning that this water, when taken up, will provide one dose of nutrient rich water to my plant.
Some nutrients will stick in the soil, and if the soil dries these nutrients stay behind. This can cause a buildup in some cases, especially in warmer weather.
Then comes the next plain watering cycle.
When I water again, I dilute the dose to 50%.
When I water again, I dilute the dose to 25%.
Even at 25% there's still nutrients present.
That is.. If we assume we don't flush the soil.

So I try not to water too often with nutrient rich water. Better even, is to not use liquid nutrients at all because of the huge amount of waste bonsai watering produces if we don't catch and reuse the runoff. Because we flush the soil, so we might wash out more and dilute it even further. To have the right osmotic nutrient content, we would need to provide nutrient rich water almost every second watering.
With the organic nutrients I give, if they're dry they don't release a lot. They mostly start wetting and releasing when I'm done watering, which is a super high dose locally that spreads out evenly over time. But it flushes out less, and that makes it way cheaper.

Bonsai should not be mistaken with hydroponics, unless you're doing hydroponics.
Great explanation, I tried not to be overly scientific since I am "sapling".
(I am trying not to be a know-it-all new guy with way too many years in production.)
 
I almost exclusively foliar feed every week or two depending upon weather. I do use osmocote, but just in the pre bonsai, most of which are in a growers mix. I know many people don't get the foliar feeding, but my experience goes back to my first nursery job when I was 13 yo. That was 62 years ago.
 
Great explanation, I tried not to be overly scientific since I am "sapling".
(I am trying not to be a know-it-all new guy with way too many years in production.)
You can do bonsai science if you want, and many here have done so themselves. I try to do so too, for most of the year.

Knowing this forum: if you're acting like a know it all, you will be called out on it. Which is not a bad thing. One has to test the waters to know how deep they are. A few here can hold a grudge, but most of us don't.
Even though I'm kind of a scientist myself, I am sometimes amazed by what people come up with and I generally think that these people help me forward my own body of knowledge.

However, it's just plants man.. I visit a lot of gardening forums and sometimes I'm blown away with the people that spend 200 dollars on trying to get that one extra tomato on their plant. The supermarket sells them for less.
The simplest techniques and the simplest thinking can get you a lifetime of fun bonsai adventures.
The most advanced techniques and the most advanced thinking can get you a lifetime of fun bonsai adventures too! But one wrong move can kill your bench. I remember Ryan Neil forgetting that compost is full of breakdown organisms and jam-packed with nutrients, killing a bunch of his plants in the yard in a double whammy; nutrient burn followed by a huge influx of harmful microorganisms. I once made a calculation error and now my favorite citrus plant will never produce fruits larger than a marble. Cmeg on the other hand is breaking boundaries I didn't know could be broken.
As long as you're having fun, it's all fair game here.
 
Absolutely true about urea, seems to have no impact on EC.
Urea is not something I use, though the landscape nursery uses it because its "inexpensive".
You also wouldn't use urea on potted plants in substrate even if you can know the concentration, because urea breakdown changes the pH and substrate cannot buffer pH as well as soil.
Yeah, urea fertilizers seem to be best used as a cheap fertilizer in agriculture.
Urea is also the go to for foliar feeding.
 
In a granular, inorganic soil like APL the vast majority of this water will drain out.
The majority will drain out and that's lost nutrients but some of that liquid solution does stay in the spaces and as a film around the particles. That's the nutrients your plant can absorb.
Most growers address the loss of nutrients by applying more often that most commercial recommendations - every week or 2. This seems to be adequate to supply nutrients needed for good plant growth but I have seen some growers increase fert to weekly with no problems.
Wasted nutrients is one of the prices we pay for using such open, well drained soil mixes.

How much of this is the plant actually getting? Are you using just enough to saturate the soil as you would with normal watering? Do you use this prepared solution for several watering sessions until the can is empty and you resume normal watering?
You'll still need to apply enough liquid to the pot to properly wet the soil and give the tree enough water to stay hydrated until the next watering. I think watering with plain water first to pre wet the soil and roots is a good idea then apply just enough liquid fert to wet the soil, not to run off stage.
I usually only apply the liquid fert once then back to plain water. Not sure whether applying more fert will cause problems or not but I don't want to find that out the hard way. Flushing unused nutrients out of the soil is important for plant health so back to plain water seems like a good idea.
 
Perhaps I need to adjust the way I fertilize. I can say I haven’t had any noticeable problems. I’m surely wasting fertilizer because it drains out.
 
I think OP is thinking about this in a way that is more complicated then it really should be.

The directions on a couple liquid fertilizers i have, the directions state to mix X amount per Y amount and apply the solution until the soil is fully saturated. Thus the amount applied changes depending on the medium's current dryness and the medium's ability to hold water.

On the basic level, by applying a liquid fertilizer, you are charging the growing medium with nutrients that the plant needs to thrive. By applying a fertilizer to bonsai substrate, the nature of the beast l dictates that we will be wasting most it. This waste will occur when you apply the solution and/or when you water with regular old H20 the next time.

So really all we are doing is just making sure that the growing medium has available nutrients for the plant to use when it needs said nutrients.

Since plants can't speak our language, we really can't tailor our fertilizers to individual trees like we can when organizing a dinner with friends. We have to watch the behavior of the plant's response and interpret those observations.

What you apply, how much you apply, and how often will be entirely specific to your conditions, products, and goals.

I apply a liquid fertilizer to my tropicals at every watering with a flushing cycle. I water approximately every 2 days give or take. When I water my trees outside, I fertilize probably once a week because I am just too lazy at the moment to mix up a fertilizer solution 5 times a day every day. I also use synthetic pellets replaced every 3 months to supplement my current process.

This in no way exact or optimal, but it is what works and fits my current life style.

Keep it simple unless you want to really take the time and and effort to do other wise. Some nutrients is a whole lot better then none at all.
 
Perhaps I need to adjust the way I fertilize. I can say I haven’t had any noticeable problems. I’m surely wasting fertilizer because it drains out.

That's the idea. We give our trees a buffet, knowing most of it will go to waste when it's washed out the next time we water. It's the cost of good soil aeration.
 
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