Does Organic fertilizer burn freshly repotted bonsai

MrWunderful

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I have always followed the rule of waiting 30 days after repotting before fertilizing. After recently researching fertilizer a bit more, I decided to switch to fish emulsion (I was using miracle gro) I also am trying to stop thinking on a “timeline”and start being more receptive to each tree’s specific needs.

I currently use a slow release like bio gold and supplement with half a dose of fish emulsion per gallon every 1-2 weeks.

In the interest of trying to view each tree less on a “timeline” I thought if I was just waiting 30 days because everything always says wait 30 days with fertilizer after repotting/root pruning as a rule (probably with inorganic fertilizer in mind) and possibly a newly repotted tree can benefit from some sort of nutrients from something considered less harsh (ie fish emulsion).

Does anyone have any experience feeding their trees with organic right after repotting? I googled it, but most articles I found were things like “top 10 fertilizing mistakes” and I was more interested in relation to bonsai specifically (a free draining inorganic soil containerized environment).

If more context is needed, I am referring to Zelkovas (I have a few I just repotted) and the buds are just opening.
 

0soyoung

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The only substance I can see to this 'advice' is that freshly pruned roots have a reduced capacity to adsorb water and minerals, so maybe some fert is just washing through that otherwise might have been utilized.

In other words I think this 'wait 30 days' stuff is non-sense.
 

papymandarin

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i agree, we waste a lot a fertilizer through washing anayway even when trees are established, and the "Fertilizer will burn new young roots" is a myth, because the absorbing part of roots (root hairs) have a life of only a few days, so the absorbing part of roots is ALWAYS young. You can choose to delay fertilizer after repotting (avoid a too explosive growth a the beginning of spring/limit abilities of the tree to grow in order to force it allocated more ressources to root growth) but it has nothing to do with a danger of fertilizer at this time.
 

sorce

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I been showing this to stir hatred for these green balls..20180327_114559_HDR.jpg

Truth is this IS a difficult situation to reproduce....
All those balls literally must have opened at the same time....and the only reason even this happened was because that concentrated powder probly sat around for some time...as nurseries rarely water so much that the concave part of the soil around the trunk fills and spills over to actually flush out these sides ....

So reproducing this with liquid chemical, or even these green balls...is NEAR IMPOSSIBLE as we water for bonsai...

So HELL NO you don't have to worry about burning anything with Organics!

I would use the fish daily....very light...but daily ..
Attracting wasps and flies daily is super beneficial .....spiders set up shop for the flies....and wasps eat other nasties that wanna start their day on your trees.
Not to mention their little yellow asses preventing things from wanting to come near in the first place!

Give us this Day our Daily Fish...

Oh I'm trying to rock a Kelp/seaweed based product Too this year....

Sorce
 

MrWunderful

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Thanks for the replies everyone. It appears I am being too cautious with fertilizing.

I think I will go back with miracle grow and alternate weekly with the fish emulsion- in addition to a cake style slow release organic.

Time to research how to make a cake style slow release, bio gold is too expensive as my collection grows.
 

GrimLore

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I think I will go back with miracle grow

This sells for 19.99USD(many places less) in a 4 pound pail. It is an actual 20-20-20 with micronutrients. I use it on most everything with no other additives and 4 pounds lasts a good while. It also foams up a lot less and settles more quickly then the Miracle Grow.

Jacks 202020 w micro.jpg

I only use one other fertilizer on Nitrogen Fixing plants that require no Nitrogen -

Bloom Blaster 20g.jpg

It is far easier and efficient and in my opinion cost effective.

Grimmy
 

MichaelS

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This sells for 19.99USD(many places less) in a 4 pound pail. It is an actual 20-20-20 with micronutrients. I use it on most everything with no other additives and 4 pounds lasts a good while. It also foams up a lot less and settles more quickly then the Miracle Grow.

View attachment 187065

I only use one other fertilizer on Nitrogen Fixing plants that require no Nitrogen -

View attachment 187068

It is far easier and efficient and in my opinion cost effective.

Grimmy
There's way too much P in both those ferts. Especially the second. There is absolutely no need for zero N fertilizers for any plant at any time. N fixing plants in pots require the same amount of N as most others. Take wisteria for example. Feed that zero N and you won't get far with it for long. The best NPK ratio for all plants is about 10 - 3- 10 or 1 - 0.3 - 1....same thing...or close to that. I love the ''science for plants bit'' under the ''Grow tech''. The science says there have been a gazillion trials done and this (1 0.3 1) gives the best plant growth generally in soilless media. Bloom booster fertilizers are bunkum. Throw the ''blossom blaster'' in the garbage where it belongs or add plenty of N and K to it to bring it back to sane ratios.
 

MichaelS

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The only substance I can see to this 'advice' is that freshly pruned roots have a reduced capacity to adsorb water and minerals, so maybe some fert is just washing through that otherwise might have been utilized.

In other words I think this 'wait 30 days' stuff is non-sense.
Agreed. Except to note that there are no root hairs to assimilate the nutrients, so it's a waste of time. A low soil salinity my help to stimulate new roots, and there is usually ample N P K in a any new mix for about 1 month of reasonable growth with nothing added. New roots from cut surfaces rely mainly on stored carbs I believe.
 

GrimLore

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There's way too much P in both those ferts. Especially the second. There is absolutely no need for zero N fertilizers for any plant at any time. N fixing plants in pots require the same amount of N as most others. Take wisteria for example. Feed that zero N and you won't get far with it for long. The best NPK ratio for all plants is about 10 - 3- 10 or 1 - 0.3 - 1....same thing...or close to that. I love the ''science for plants bit'' under the ''Grow tech''. The science says there have been a gazillion trials done and this (1 0.3 1) gives the best plant growth generally in soilless media. Bloom booster fertilizers are bunkum. Throw the ''blossom blaster'' in the garbage where it belongs or add plenty of N and K to it to bring it back to sane ratios.

Think and do as you wish, works for me and others for many years, some quite noted in Bonsai... And more specifically that solution was offered to the OP... Not certain why you are popping in to disagree with people. Have a nice day ;)

Grimmy
 

MichaelS

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Think and do as you wish, works for me and others for many years, some quite noted in Bonsai... And more specifically that solution was offered to the OP... Not certain why you are popping in to disagree with people. Have a nice day ;)

Grimmy
Here we go. Why is it that whenever the facts are pointed out many people get there nose out of joint.
I didn't ''pop in'' to disagree but to set the record straight about what people think is right and what actually is right. I thought this forum was all about that sort of thing. Doesn't matter who told you what, if it's wrong it's wrong.
No one can know what the truth is until it is made available to them.

Typical concentration of nutrients in plant leaves...

P1120079.JPG



Typical NPK in flowers

P1120077.JPG




P/N ratios in a range of plants. (to get the ratio of P to N just divide the % of P x the % of N......... in a fertilizer or in a leaf)
As you can see, in Azaleas for example, the ratio is very low. Fertilizers should be around this kind of range for best growth.


P1120076.JPG


High P reduces growth and in many cases reduces flowering.
As we can see here.....

P1120078.JPG


Your 20 20 20 is in fact N 20 P 8.8 (the rest is oxygen) K 16.6 (the rest is oxygen)
The P/N ratio of this is....20 divided by 8.8 = 0.44. Double or triple what is needed.

Ok so now you have the facts you can of course do what you want.
 

MichaelS

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A bit more... You can work out the ratios for yourself but I'll do the rose for you. The P/N ratio is 0.2.
If you are happy to think that the former advice given to you is better than scientific trials where millions of dollars are at stake, go for it!
Optimum ratios = any more or any less of anything reduces growth.

P1120080.JPG
 
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Stan Kengai

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Fertilizer wars! Gotta love 'em.

I couldn't tell you whether the science/reasoning behind @MichaelS posts is valid or not. But I do know that scientists have shown that high concentrations of Phosphorus inhibit the growth of mycorrhizal fungi. As further anecdotal evidence, I have never seen better mycorrhizal growth then when I use a completely organic fertilizer regimen. That's my two cents.
 

Anthony

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@MichaelS ,

first a big thank you. The Poui is in bloom and the yard is yellow.
So we are composting the tons of leaves and some flowers.
Had no NPK for flowers ------- the information you left will average out just fine.
__________________________________________________________________________________-

Latest read says ------- Low phosphorous is better as fertiliser goes.
So we continue to use 1/3 strength of Miracle Gro Lawn Fertiliser once a
week into moist soil.

Additionally, a wise man on AusBonsai ------ had this to say.

If you repot, the fresh soil mix if it has compost/organic matter, should
have enough food for the tree for a month.
According to Texas edu. compost will release N for 4 years.
Probably half that in a Tropical climate - maybe 2 years.

So nothing wrong with waiting a month to start fertilisings ------ if your
soil mix has an organic.

Plus you did cut off a % of the fine feeder roots [ which might restart
in 24 hrs, but what is the rush ? ]

As always remember -------------

" We grow our Bonsai for Beauty, not Produce or Lumber."
________________________________________________________________________

So the range for finished bonsai [ maybe refinement stage as well ]
is around 6 N and low P and K [ maybe 1 or 2 ] plus micro.
Remember the American have ratings for K20 and P204 [ or is that 3 ? ]
The UK and Europe [ Australia ? ] have it as K and P on the bag of
fertiliser.
Good Day
Anthony

* now ask yourself does your soil have organic matter and re-adjust
for information being supplied.
 

GrimLore

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Ok so now you have the facts you can of course do what you want.

I understand and have studied those things and appreciate that you have shared that information, not sarcasm but honest.

What I find "works" in a variety of potted plants, in a wide variety of substrates is different so my methods here are different then textbook as well as MANY others. Not an argument, just a basic easier way that I implement, tried and true.

Grimmy
 

MichaelS

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@MichaelS ,

first a big thank you. The Poui is in bloom and the yard is yellow.
So we are composting the tons of leaves and some flowers.
Had no NPK for flowers ------- the information you left will average out just fine.
__________________________________________________________________________________-

Latest read says ------- Low phosphorous is better as fertiliser goes.
So we continue to use 1/3 strength of Miracle Gro Lawn Fertiliser once a
week into moist soil.

Additionally, a wise man on AusBonsai ------ had this to say.

If you repot, the fresh soil mix if it has compost/organic matter, should
have enough food for the tree for a month.
According to Texas edu. compost will release N for 4 years.
Probably half that in a Tropical climate - maybe 2 years.

So nothing wrong with waiting a month to start fertilisings ------ if your
soil mix has an organic.

Plus you did cut off a % of the fine feeder roots [ which might restart
in 24 hrs, but what is the rush ? ]

As always remember -------------

" We grow our Bonsai for Beauty, not Produce or Lumber."
________________________________________________________________________

So the range for finished bonsai [ maybe refinement stage as well ]
is around 6 N and low P and K [ maybe 1 or 2 ] plus micro.
Remember the American have ratings for K20 and P204 [ or is that 3 ? ]
The UK and Europe [ Australia ? ] have it as K and P on the bag of
fertiliser.
Good Day
Anthony

* now ask yourself does your soil have organic matter and re-adjust
for information being supplied.
Hi Anthony

Yes I still don't understand why US fertilizers continue to use the archaic % P205 and K20. It is misleading to people who will assume they are getting 20% P for example when they are not. 20 20 20 would be a good fertilizer for use in soil where you have a percentage of clay which will make some of the P unavailable. The high P seems to be a hangover from when potting mixes were mainly top soil. These days you just don't need it. (unless you use soil that is - which is not necessarily a bad thing!) You are correct about the N from compost but we usually need to add more for fast growing container plants - as you are doing with the lawn food.
 
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