Fertilising - foliar vs soil

Hello everybody, I was reading about rate of fertiliser absorption (re: The living art of bonsai, Amy Laing, p. 185).

I’m impressed about the (vastly) superior rates of foliar vs soil feeding and I was wondering whether this is something you have experienced/practised?

Alternation of feeding methods is recommended to avoid weakening of roots; would it still be possible to combine liquid fertiliser spraying with solid fertiliser feeding?

Thank you for your advice.

Y.

With foliar feeding look up what can be absorbed by the leaf and will flow
on into the system.
Also what is too large and sticks where it goes.
Good Luck
Khaimraj

Thank you for your help.

Y.

Also, your pines and junies will really enjoy foliar feeding in addition to your regular soiliar feeding...

Thank you for this. I also have maples and a Japanese March and I was wondering if this works for them too please?

Also, I would be using granular fertiliser (e.g. green dream) and I’m concerned I may overdo it doubling the dose. Would it be better to alternate liquid soliar-liquid foliar?

Thank you for your help!

Y.

I would not really consider that "doubling the dose"... organic granular works very slow and gently from the roots up while i believe that foliar feeding is more quickly accessible to the tree (and just as quickly disposed of)...

Cool! Thank you Kevin for this.

Kind regards,

Y.

Yamato wrote:Hello everybody, I was reading about rate of fertiliser absorption (re: The living art of bonsai, Amy Laing, p. 185).

I’m impressed about the (vastly) superior rates of foliar vs soil feeding and I was wondering whether this is something you have experienced/practised?

Alternation of feeding methods is recommended to avoid weakening of roots; would it still be possible to combine liquid fertiliser spraying with solid fertiliser feeding?

Thank you for your advice.

Y.

First it's important to note that foliar feeding is *not* superior to feeding the roots, also that many nutrients are not even able to be absorbed *at all* by the leaves. Whoever said "alternation of feeding methods is recommended to avoid weakening of roots" isn't someone I'd take anymore advice from :/

But yes there's no problem doing both, when I fertilize (I use a dissolved liquid fert) I splash it on the crowns as well as soaking the substrate, the thing is though the leaves don't uptake nutrients remotely in the manner you're describing here, the roots do the heavy lifting here and you could really lead yourself/your trees down a bad path if you're operating under the idea that leaves are comparable (or 'vastly superior') to roots for nutrient-uptake, if that's truly how the book portrayed it I'd ditch that book because there's no telling what other things are wrong that you may take as legit only to find out later, maybe at a great loss, that they weren't

[btw I'm new here, could anyone tell me the easiest way to see what threads you've posted in that have new replies? Kind of like a 'control panel' on bbcode boards?]

Thank you for your thoughts.

In the book “The living art of bonsai” by Amy Laing the following statistics on rate of fertiliser absorption are provided:
- Soil: N 50%-70%, P 45%, K 40-50%
- Foliar: N 95%, P 54%, K 80%

It would be great to share suggestions on books/research on this point.

Kind regards,

Y.

P.S. Sorry I can’t help with your question on the forum

Yamato wrote:Thank you for your thoughts.

In the book “The living art of bonsai” by Amy Laing the following statistics on rate of fertiliser absorption are provided:
- Soil: N 50%-70%, P 45%, K 40-50%
- Foliar: N 95%, P 54%, K 80%

It would be great to share suggestions on books/research on this point.

Kind regards,

Y.

P.S. Sorry I can’t help with your question on the forum

Rates of absorption are *all over* the place, for instance just with nitrogen you can't give a blanket rate as urea has a different rate than ammonia nitro, and even when apples-to-apples in that regard it can vary in different containers based on pH, based on humic/fulvic acids, based on what % of container absorption happens via direct root-uptake versus mycellial hyphae...am starting to think it's fruitless to come up with charts and that it's something to be googled for any particular ingredient...

In general though, when in the context of our low-CEC, rapid-draining & frequently flushed bonsai-containers, I think that *consistency* of application is of huge importance- for instance, I was using an instant-release every third day, and I water 3x/day, so that means I'd fertilize once and then flush it ten times before fertilizing again....hard to think there's much fertilizer left on that last flushing before the subsequent fertilization! To combat that problem I got some 15-9-12, "6-month release" Osmocote, am using that at a pretty solid rate (aiming to make it ~75% of my fertilization) and am now just doing instant fert every fifth day as a boost, am planning a 'booster' application of Osmocote about 2-2.5months after the initial application (as I'm essentially considering it a 4mo product w/ a pretty quick decline past the halfway point, as the pellets are just coated w/ polymers and not mixed w/ polymers to provide true 'extended release') Am applying micro's and epsom salt with the fert every 5th day as well, and things are growing about as fast as I imagine they're capable of! I think correcting the pH made a big difference, I've been using rainwater (have a 150gal+ collection setup now ) mixed with tap, rain is 4pH and tap is 8pH so half/half gives me the slightly-acidic 6 that plants seem to thrive on!!

Question Yamato,

what are using this fertiliser information towards,

[1 ] Trunk thickening ?

[2] Refinement ?

[3] Maintaining ?

The google would have shown you that some oxide nutrients cannot
fit into, or move around in a leaf.

Presently research is showing limits of 12 to 6 N and a very low % of
K2 and P [ note not K20 or P203 r is that 04 ] as around 2 or 3.

Might take some time and read at Garden Myths [ google ]
Laters.
Khaimraj

Bougies!!1!1!!! wrote:

Yamato wrote:Thank you for your thoughts.

In the book “The living art of bonsai” by Amy Laing the following statistics on rate of fertiliser absorption are provided:
- Soil: N 50%-70%, P 45%, K 40-50%
- Foliar: N 95%, P 54%, K 80%

It would be great to share suggestions on books/research on this point.

Kind regards,

Y.

P.S. Sorry I can’t help with your question on the forum

Rates of absorption are *all over* the place, for instance just with nitrogen you can't give a blanket rate as urea has a different rate than ammonia nitro, and even when apples-to-apples in that regard it can vary in different containers based on pH, based on humic/fulvic acids, based on what % of container absorption happens via direct root-uptake versus mycellial hyphae...am starting to think it's fruitless to come up with charts and that it's something to be googled for any particular ingredient...

In general though, when in the context of our low-CEC, rapid-draining & frequently flushed bonsai-containers, I think that *consistency* of application is of huge importance- for instance, I was using an instant-release every third day, and I water 3x/day, so that means I'd fertilize once and then flush it ten times before fertilizing again....hard to think there's much fertilizer left on that last flushing before the subsequent fertilization!  To combat that problem I got some 15-9-12, "6-month release" Osmocote, am using that at a pretty solid rate (aiming to make it ~75% of my fertilization) and am now just doing instant fert every fifth day as a boost, am planning  a 'booster' application of Osmocote about 2-2.5months after the initial application (as I'm essentially considering it a 4mo product w/ a pretty quick decline past the halfway point, as the pellets are just coated w/ polymers and not mixed w/ polymers to provide true 'extended release')  Am applying micro's and epsom salt with the fert every 5th day as well, and things are growing about as fast as I imagine they're capable of!  I think correcting the pH made a big difference, I've been using rainwater (have a 150gal+ collection setup now ) mixed with tap, rain is 4pH and tap is 8pH so half/half gives me the slightly-acidic 6 that plants seem to thrive on!!

Thank you for your message: very interesting and useful!

I’m currently combining “organic” solid feed (granular, renewed every 4 weeks) with “synthetic” from time to time (kind of weekly) to tackle low-CEC soil mix.
I was considering the use of 1/4 strength solution as Chempak suggests and use this mild solution at every watering but I’m concerned about over-feeding and this is when I became interested in foliage feeding.
I wonder if I can drop the solid feed and go just with the mild solution?

Thank you!

Y.

Khaimraj Seepersad wrote:Question Yamato,

what are using this fertiliser information towards,

[1 ] Trunk thickening ?

[2] Refinement ?

[3] Maintaining ?

The google would have shown you that some oxide nutrients cannot
fit into, or move around in a leaf.

Presently research is showing limits of 12 to 6 N and a very low % of
K2 and P [ note not K20 or P203 r is that 04 ] as around 2 or 3.

Might take some time and read at Garden Myths [ google ]
Laters.
Khaimraj

Hello Khaimraj, thank you for your message.
My interest is in the general aspect of feeding as I have trees at different stages of development.
Thank you for your suggestion: I will certainly look into it.

Kind regards,

Y.

Yamato wrote:
Thank you for your message: very interesting and useful!

I’m currently combining “organic” solid feed (granular, renewed every 4 weeks) with “synthetic” from time to time (kind of weekly) to tackle low-CEC soil mix.
I was considering the use of 1/4 strength solution as Chempak suggests and use this mild solution at every watering but I’m concerned about over-feeding and this is when I became interested in foliage feeding.
I wonder if I can drop the solid feed and go just with the mild solution?

Thank you!

Y.

NP, my pleasure

I'm doing something similar to you right now (using a solid + liquid fert regimen), I apply my instant/liquid fert more often than weekly (I was doing every 3rd day before I got solid ferts, now I'm doing...well I was supposed to do every 5th-7th day but have been doing every 3rd-5th day despite having applied a lot of timed-release Osmocote, things are growing VERY fast!!)

Would need to read 'chempak's full idea on this but, generally speaking, yes that's as on-point as I can see! We use media that's of a structure (ie having a minimum-particle-size) that doesn't hold much water, and the nature of the particles themselves doesn't really help things (ie, their low CEC values), so when you consider that a plant wants *constant* availability of nutes, the idea of timed-release makes a ton of sense....honestly I'd take a medium-dosage timed-release over a larger-dose, once-weekly formula (I don't know about your climate, but if it's not raining then I need to water 3x daily, so even using liquid fert every 3rd day means that I'm applying fert once, then flooding-out 9 times with water, then fertilizing again- in our containers this is under-, not over-, fertilization!)

I can't advise enough that you keep that solid feed on there, it's a great way to ensure there's always some nutrients when the tree needs it, I've aimed to make my Osmocote pellets ~75% of my total fert regimen, and the rest is liquid which is nice since I can play around w/ application days, for instance if it's gong to be sunny the next 3 days I may give extra liquid fert, if it's going to be cloudy/rainy I may skip a scheduled liquid-fert, I like that ability to control things *to a degree* while knowing that the osmocote is making-sure the plants are never in a water-only container!

Yamato wrote:
I was considering the use of 1/4 strength solution as Chempak suggests and use this mild solution at every watering but I’m concerned about over-feeding and this is when I became interested in foliage feeding.

I wish I could remember where I found someone who did some rough math and came to the #'s of how effective foliar-feeding is *in the context of* an established (not necessarily *old*, just properly established ie it's got a solid enough root-ball) specimen, it's NOT very much at all, foliar is something that people would be exploiting hard if it were able to increase nutrient uptake AND usage above&beyond what the roots of a healthy, vigorous tree will take from a heavily-fertilized medium... anyway I came back to post again because I wanted to emphasize how vital THIS article is:

http://walter-pall-bonsai.blogspot.com/2010/06/feeding-substrate-and-watering-english.html

this ^ article explains fertilization very, very well BUT it does so in the context of watering&substrate and it explains why that's not "a bonus" but is requisite, why watering/substrate/fertilization are to be viewed as a single overall thing that's a composure of 3 separate-but-interrelated things. The reason I came back thinking to share this is because your line of "concerned about over-feeding" is something I'd felt myself when I was pushing-up my fert levels, however I used some "throw-away" trees (my real pet-name for them is an expletive so I'll just call them 'throw-aways', ie trees I don't like / will never be good bonsai / I can't bring myself to just throw away!) as material for an "A/B testing", trial-and-error approach to upping fertilizer, what I'd do is up the fert doage of my beotch-trees for a week or two and gauge their growth habits *before* I'd put the rest of the garden up to that level - kind of using them as "canaries in the coal mine", to let me know if/when I over-fertilized. I got nothing. I hit a point where I was sure I was just wasting fertilizer, and no plants were suffering they were all just thriving- this got me thinking I could've added another 50% *from that level* and still had no problems, it contradicted my "what if I over-fertilize?" mindset so much that I was starting threads about the nature of salt-buildup and its mechanism of action/damage to roots and things of that nature, because I just couldn't believe it but it was true- I could pour so much miracle gro on my bougies/crapes/ficus/bald cypress that it seemed impossible to over-dose, so now I simply aim for what I consider to be ~120% of what the tree really needs, knowing that some extra fert just falls-out of my loose, low-CEC substrates, won't ever worry about this specter of "over fertilizing" again (at least in the context of MY garden- I want to make clear that I grow tropicals in FL, and my bald cypress are my only conifers- if you're in colorado growing pine trees I'd have no idea what to say, this is just what's held true for broadleaf trees for me, actually me + others ie the guy who wrote that article I linked, I cannot overstate how invaluable it is to understand that article forward and backward, I feel like I *do* and I still re-read it time to time )

Thank you so much for sharing the article and your thoughts and experience.

I’ve been paying greater attention to alternative soil “recepies” and different feeding regimes and I found your tips very useful.

Kind regards,

Y.

Foliar feeding vs soil fertalizing depends on the species of tree mainly. Pines and junipers uptake more nutrients through foliar feeding than deciduous species, mainly due to the differance in leaf type. Quick feeding chemical fertilizers such as miracle grow are never ever recommended for bonsai. Slow release organic fertalizers are best for our trees if soil fertilizing. They release food slowly over time with little root shock like chemicals. Organic water soluables like bone meal, fish emulsion and super thrive are great for foliar feeding. Mixing them in a sprayer and setting it to mist mode will give smaller water droplets and better absorption. Aim for the underside of the leafs where uptake truly occurs, normally before or after the sun is out. These pores/stomatas close tightly during the day and open larger for better absorption during the evening/ early morning. It is best to use a combination of 2-3 differant fertilizers. Different plants have differant needs as well.
Trunk thickening for bonsai is normally obtained by field growing a tree; planting it in the ground for a few years without pruning. Restarting the bonsai reduction process after the trunk size is obtained. Trees hardly gain trunk girth within a bonsai pot due to the restriction of the roots. Younger trees you want to increase pure size of will need higher nitrogen content in your feed. Refinement and maintaining your older trees will need a more balanced feed without high nitrogen, which will cause excessive growth.

Bougies!!1!1!!! wrote:

Yamato wrote:Hello everybody, I was reading about rate of fertiliser absorption (re: The living art of bonsai, Amy Laing, p. 185).

I’m impressed about the (vastly) superior rates of foliar vs soil feeding and I was wondering whether this is something you have experienced/practised?

Alternation of feeding methods is recommended to avoid weakening of roots; would it still be possible to combine liquid fertiliser spraying with solid fertiliser feeding?

Thank you for your advice.

Y.

First it's important to note that foliar feeding is *not* superior to feeding the roots, also that many nutrients are not even able to be absorbed *at all* by the leaves.  Whoever said "alternation of feeding methods is recommended to avoid weakening of roots" isn't someone I'd take anymore advice from :/

But yes there's no problem doing both, when I fertilize (I use a dissolved liquid fert) I splash it on the crowns as well as soaking the substrate, the thing is though the leaves don't uptake nutrients remotely in the manner you're describing here, the roots do the heavy lifting here and you could really lead yourself/your trees down a bad path if you're operating under the idea that leaves are comparable (or 'vastly superior') to roots for nutrient-uptake, if that's truly how the book portrayed it I'd ditch that book because there's no telling what other things are wrong that you may take as legit only to find out later, maybe at a great loss, that they weren't

[btw I'm new here, could anyone tell me the easiest way to see what threads you've posted in that have new replies?  Kind of like a 'control panel' on bbcode boards?]

The problem is in the perception. True that there are probably some nutrients the leaves will not accept unless you find a way to only apply it to the foliage much of it is going to be absorbed through the roots just by the fact it got on the surface by way of the activity of putting it on the tree. Personally I would like to know which elements are not absorbable through the leaves that would exclude foliar feeding in your mind.

Yamato wrote:Thank you so much for sharing the article and your thoughts and experience.

I’ve been paying greater attention to alternative soil “recepies” and different feeding regimes and I found your tips very useful.

Kind regards,

Y.

My pleasure I actually just setup my first styrofoam-aggregate container the other day, I slip-potted a root-bound crape myrtle into a styro and styro+pine-bark mixture, will be interesting to see how it goes (have heard of using styro like this before and figured it was worth a try when I was walking a box of styro peanuts to the trash ;D )

Mrhagan23 wrote:Foliar feeding vs soil fertalizing depends on the species of tree mainly. Pines and junipers uptake more nutrients through foliar feeding than deciduous species, mainly due to the differance in leaf type. Quick feeding chemical fertilizers such as miracle grow are never ever recommended for bonsai. Slow release organic fertalizers are best for our trees if soil fertilizing. They release food slowly over time with little root shock like chemicals. Organic water soluables like bone meal, fish emulsion and super thrive are great for foliar feeding. Mixing them in a sprayer and setting it to mist mode will give smaller water droplets and better absorption. Aim for the underside of the leafs where uptake truly occurs, normally before or after the sun is out. These pores/stomatas close tightly during the day and open larger for better absorption during the evening/ early morning. It is best to use a combination of 2-3 differant fertilizers. Different plants have differant needs as well.
Trunk thickening for bonsai is normally obtained by field growing a tree; planting it in the ground for a few years without pruning. Restarting the bonsai reduction process after the trunk size is obtained. Trees hardly gain trunk girth within a bonsai pot due to the restriction of the roots. Younger trees you want to increase pure size of will need higher nitrogen content in your feed. Refinement and maintaining your older trees will need a more balanced feed without high nitrogen, which will cause excessive growth.

I dislike seeing it as "versus", foliar feeding is something you may want to go for *after* you're sure you've nailed regular fertilization.

You mention the stomata are closed during the day- could you elaborate on that? I was totally thinking the stomata were part of the transpiration process and actually *more* active during the day! I need to do another round of wiki-botany lessons ;D

Agree re nitro on refinement, though in my case I'm just developing stuff (only have stock&pre-bonsai, not a single 'real' bonsai!) so the excessive growth is desirable and the increased internode length isn't a problem at this stage thankfully!

I can't say I agree with your take on chemical fertilizers, walter pall seems to use them quite effectively and in my experiences they've been very useful, though at this point I'm doing a good portion of my feeding via timed-release osmocote (and then adding instant-release miracle-gro every ~4-6d at maybe 5% nitro- to be clear though I'm growing tropicals in FL so this probably wouldn't be smart for growing conifers in CO!)

Vance Wood wrote:
The problem is in the perception. True that there are probably some nutrients the leaves will not accept unless you find a way to only apply it to the foliage much of it is going to be absorbed through the roots just by the fact it got on the surface by way of the activity of putting it on the tree. Personally I would like to know which elements are not absorbable through the leaves that would exclude foliar feeding in your mind.

I don't have anything specific in-mind, I know there's varying degrees of absorption but that's not really my 'gripe' with foliar-feeding - in fact I can't say I have "a gripe" as I have a mister-bottle outside with MG 24.8.16 in it right now, diluted of course but a strong nitro fert with epsom[Mg+ & Su] salts and iron/cal mix, I just don't think there's much (any?) value to it for a deciduous tree that's *already* getting optimal nutrients through the roots - do you happen to know if it's ever been established that you can increase the total-nutrient-uptake of a tree beyond what the roots can do? My understanding was that, say for iron, if the tree has enough iron from the roots then foliar applications would be utterly useless....I have two mister-bottles out back and use the one with fert for things like cuttings, or a collected item that's still got foliage but doesn't have established roots yet, in those cases I see value to using it but when I look at one of my crapes or bougies that's in a substrate that's got Osmocote timed-release, and is getting hit with miracle-gro more than 1x/wk, I just can't help but think that they're getting *more* nutes than they're actually using and that *that* means, inherently, that foliar feeding would be of no use here - if the roots can get everything they desire, there's no 'boost' by foliar feeding, is how I understood it - if I'm wrong I'd love to know, as I've got some key trees I'm looking to push growth on and would definitely start foliar feeding on top of what I already do, I was just under the (possibly false) assumption that *if* needs are 100.0% met then there's no benefit from foliar, you can't push the trees to 105% capacity is the logic I guess, but if I'm wrong I'd definitely want to know!