Rethinking (sort of) fertilization

I recently read a Walter P blog on fertilization in which he points out that generally people do not feed their bonsai nearly enough. In short, he points out that people tend to follow old recommendations for feeding protocols that depend on heavier soil mixes and "regular" container gardening instead of the heavy aggregate mixes most of us use for our trees. Then he suggests that he feeds his trees about "20 to 60" times more than the average person does.

Well, I'm that average person and I've long suspected that I was significantly underfeeding my trees as Walter suggests. But, I'm also leery of overfeeding and creating a toxic environment in the soil.

I'm really wondering how often you all are feeding your trees?

Well, whatever the outcome of this discussion may be, you don't need to worry about that "toxic environment." If your trees' soil has decent drainage (or, actually, any at all), we water frequently enough to wash away any toxicity.

What Walter is proposing sounds a lot like Michael Persiano's "Superfeeding" regime.

My reaction to both: Whatever works for you. If your trees are health (i.e. green and growing, but not too fast -- they ARE bonsai, after all) you're probably doing OK. Trees tend to use what they need and let the rest flow out the drainage holes.

I'd like to question the idea that free flow soil will not prove toxic . It's so complicated especially where there is a build-up of salts from liguid fertilizers.

The speaker at our recent club meeting hosted a "Stump the Chump" where club member brought problem trees for analysis. One tree was a small Japanese maple that had leaves that were burned just around the edges. The speaker,a bonsai teacher from the south, suggested the tree could have a build-up of salts. And for further protection the tree should be put in partial shade. He went on to discuss his remedy for these salts and gave us a recipe for a gypsum wash. He also pointed out that this occurred in bonsai that had not been recently repotted.

My question is has anyone used gypsum as a remedy for salts? And does organic fertilizer also create salt build-up?

The recipe : Soak a tablespoon of garden gypsum/ 1 gallon of HOT water overnight. Shake the mixture. The next day shake the mixture again and water those bonsai that have salt build-up symptoms. The next regular watering should drench the trees to wash out the salt.

Norma

A skeptic wants to know: Just what are these "salts" and what do they form from? A bit of chemistry please.

I've heard of these mysterious "salts" for as long as I've done bonsai -- which is a while now. I've asked extension officers about them and got an I've-never-seen-that response. Or, they've said you'd have to spray/apply 100X the label dose to get that kind of reaction.

Salt buildup can be a problem in heavily cropped and badly maintained and irrigated cropland -- as in the California central valley -- but I've found no one (who has a background I'd trust to know whereof he or she speaks) to give me the chemistry of what might cause a toxic salt buildup in bonsai soils. You'd have to be an amazingly unobservant and careless person to cause it.

It always sounds to me like one of those "facts" that have been passed on from mother to son until they suddenly become true -- not quite as bad as the drop-of-water-burning-holes-in-leaves tale, but similar.

The first thing to know is that fertilizers are salts.

However, salt buildup should never be a problem with proper watering and proper drainage, as the salts just get flushed out the drainage holes. I know a few bonsaists, such as Guy Guidry, that use fertilizers, such as miricle grow, everytime they water without salt buildup.

A good article on this subject can be found at http://ag.arizona.edu/pubs/garden/mg/soils/applying.html



Will

ha ha, you guys are funny...

It be like me talking about winter storage... we just don't have the right context.

Zone 9-10 Southern California, in fact all over this the desert Southwest, our water is highly alkaline, eight, pH 8+. We have a constant battle with alkaline salt buildup.it's not always visible like big Salt Licks, but a gradual turning of the soil, So alkaline, that it will take up nutrients. So one of the best ways to counteract is gypsum, acidic fertilizer , like cottonseed meal, and a constant flushing of soil and scrubbing pots.


Believe me when you've gone for 6 to 8 months without a drop of rain from the sky things tend to get crusty, amazingly, though. When the rains to come, well It is the greatest of all decrustifiers.. LOL

waiting for the rains to come
your old pal
rock

Rock wrote:ha ha, you guys are funny...

It be like me talking about winter storage... we just don't have the right context.

Zone 9-10 Southern California, in fact all over this the desert Southwest, our water is highly alkaline, eight, pH 8+. We have a constant battle with alkaline salt buildup.it's not always visible like big Salt Licks, but a gradual turning of the soil, So alkaline, that it will take up nutrients. So one of the best ways to counteract is gypsum, acidic fertilizer , like cottonseed meal, and a constant flushing of soil and scrubbing pots.

Well, for you "superfeeding" may well be necessary.

Just to be clear .... Rock's discussion of alkaline salt build-up is something of which I'm very familiar. I've usually called it "mineral deposits" or the results of high calcium in my city's water which comes from aquifers.
This seems different than fertilizer salts or do they interact to produce the same problem?

Thanks Will, for the interesting report by Arizona Ag./edu. So there is such a thing as SALT deposits in potted plants! And it seems several variables : amount of watering, soil components, and type plus frequency of fertilizer use.

So is there no universal answer or must we experiment in our own little eco-sphere ?

Norma

A one-size-fits-all answer should always be questioned! And they'll be wrong more often than not.

But this isn't a problem I'd worry at all about for your bonsai.

I think you must also consider just how much growth you want from your trees. For trees in early developement, rapid growth promoted by feeding allows for more branching. But, in older trees it disrupts the tree's mature form.......................

Yes, but I see a consensus developing against traditional advice that aggressively fertilizing your trees won't result in a caustic/toxic environment for your trees.

Following traditional advice very well may have contributed to the generally mediocre results I have experienced with many of my trees over the years. I've even lost some that I couldn't really understand why, no visible disease, etc.

So what's really too much. How often do you actually feed and at what general strengths?

Hi Michael
I know someone who piles Rooster (chicken poop fertiliser) onto his trees in Spring, and when it goes crusty he takes it off....and puts more on. His trees grow like, well, like very bushy things. It depends how much you want your tree to grow. I think you can burn the roots if you have your liquid feed too concentrated, but with slow release fertiliser, if you want your tree to grow a lot, feed it a lot. M Persiano's superfeeding regime has been tried and tested!
J

It was Walter's comment that 99% of bonsai are in development that caught my attention because 100% of my trees are in development. I've been wanting better growth from season to season and just never really achieved it.

How often do you actually feed and at what general strengths?

My fertilization regime can be be described as "haphazard."

I try to apply it at close to label recommendations, but don't weigh the stuff out. In the spring, I fertilize as soon as my earliest trees start to have swelling buds, then again 2 weeks later.

I probably fertilize everyone no more than 3 times for the remainder of the summer. I may dose a tree or two once in between, depending.

I give a last dose of fertilizer to my trees just as maple leaves start to fall.

Period.

The danged trees still put out too much new growth.

I think we all agree that it depends on where you live!!!!! and even at that you have to take into consideration the weather conditions that you have throughout each growing season. Here in the PNW where we get 60-80" of rain a year I fertilize every two weeks....which is based on my learnings from this and other forums.....so when I get paid....so do my trees and this year I've achieved a noticable change in colour and growth.
Cheers Gman

gman wrote:I think we all agree that it depends on where you live!!!!! and even at that you have to take into consideration the weather conditions that you have throughout each growing season. Here in the PNW where we get 60-80" of rain a year I fertilize every two weeks....which is based on my learnings from this and other forums.....so when I get paid....so do my trees and this year I've achieved a noticable change in colour and growth.
Cheers Gman

Just for clarification, you stated, "...I've achieved a noticable change in colour and growth"; what exactly is changing color and/or growing? (ie: Your income, your trees, yourself or all of the above)

I have noticed a significant number of bonsai enthusiasts in the PNW, I am jealous. Although, the Midwest numbers are growing.

Jay

Hi Jay,
The changes I was speaking of, has been in my trees (alas my income has gone the other way).
Like most without a lot of expereince in this art, I searched the websites, purchased books and asked a lot of questions in regards to soils types and fertilizer regimes and with lots of trial and error during 2007 and 08 I started a more concentrated effort in 2009. I started applying humic acid and both organic and inorganic fertilizers (liquid and slow release) and I've really seen my conifers change ....with a deepened colour (a deep blue/green) and they just look way healthier than in previous years.
Cheers G.

Regarding salt buildup, take it or leave it, Walter Pall in his Blogger says:

"Too much salt in the substrate is almost impossible if one waters aggressively every day. Even azaleas don't mind my treatment. They thrive very well with very hard water, ordinary baked loam and peat as the substrate and aggressive feeding like all the rest of the trees. " - Walter Pall

"I have learned and experimented a lot in the meanwhile and I use my method with hornbeams with GREAT results. The key is aggressive watering that will wash out the excessive salt." - Walter Pall comments on super feeding and watering regime applied to all his trees.

You can read a great post by Walter Pall "Feeding, Substrate and Watering" here:

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

Whilst I have an immense amount of respect for Walter...what works for him will not necessarily work for anyone else unless they duplicate the tree...the soil...and finally the climate.

I'll stick to what works for me and works well before rushing out to make any changes.

Mike

Mike,

You raise a very important point which I had completely overlooked. I did state take it or leave it but I suppose Walter's approach would work given you use similarly porous substrates and at least four similar seasons throughout the year. Not everyone would be coming to the table with the same parts in place unless, like myself, they've chosen to duplicate the approach. Here in North Texas, these summers have been known to be blistering hot so I'm using the most porous substrate, power feeding, and watering regimen with great success.

I can't imagine fertilizer causing a problem if you read the label on the package and water your trees regularly.

People tend to make fertilization into something mystical. It's not.

EVERYthing (probably more than) you need to know is here: http://www.evergreengardenworks.com/fertiliz.htm

I must admit I'm a beginner when it comes to Bonsai but I do know a thing or two when it comes to water as we own a Salt water Reef aquarium business.

When it comes to corals water impurities like minerals will definitely affect their health...some minerals like the magnesium act a bit like calcium and the corals enjoy it but other minerals will cause damage.

In salt aquariums there is allot of evaporation because of the heat from the metal halides lighting which could compare to allot of evaporation from our planters in the hot sun...The water will evaporate but the minerals do not, therefore they accumulate every time we add more water in the fish tank / planters.

Having your water professionally tested for all impurities will give you an idea if this would be a concern in your own area. If you do have allot of heavy metals this is where it may become a problem and in aquariums water changes (replacing water often instead of just topping off when evaporation occurs) may be the equivalent of changing the soil in planters to remove excessive metal/mineral deposits.

However, there is an easier way of solving the problem but it does cost a bit of money to get set up... We use RODI units that take all impurities out of the water including all minerals...we then use specially prepared supplements and trace elements that are 100% all good for the corals and inverts...we've got test kits for calcium and others to get the proper levels wanted for the different types of corals' needs. I would assume that the same thing would be possible for trees and plants...through adding all nutrients through fertilizers that are specific to their individual needs without adding unwanted harmful metal/mineral deposits that may be present in some waters.

Once you get the hang of RODI units you can install auto top off/ shut off systems...we use a big garbage bin out of a special type of plastic that does not dissolve bad chemicals in the water over the yrs...corals are very sensitive and we've seen the results of these toxins. It's a bit like ABS plumbing and using a garden hose for drinking water source...a plumber might loose his license hehe! When you know what to look for you can find them at a local hardware stores...a good indicator are the ones that are out of hard plastic and not the ones that you can alter their shape (more flexible/rubbery texture). When the garbage can is full there is a floater that shuts off the water at the desired level and when I remove a bucket or pump out some water the float goes back down in the garbage can letting new RO water to fill for the next watering without over spilling.

I know this is not directly answering to the fertilizer question but I believe it can help wash out excess fertilizer without adding to the potential problem of over fertilizing and creating a better soil environment of minimizing the build up of mineral salts deposits.

Sorry about such a lengthy post and I hope these tips can help some of you who "do" have a water problem.

Carole

Rock wrote:ha ha, you guys are funny...

It be like me talking about winter storage... we just don't have the right context.

Zone 9-10 Southern California, in fact all over this the desert Southwest, our water is highly alkaline, eight, pH 8+. We have a constant battle with alkaline salt buildup.it's not always visible like big Salt Licks, but a gradual turning of the soil, So alkaline, that it will take up nutrients. So one of the best ways to counteract is gypsum, acidic fertilizer , like cottonseed meal, and a constant flushing of soil and scrubbing pots.


Believe me when you've gone for 6 to 8 months without a drop of rain from the sky things tend to get crusty, amazingly, though. When the rains to come, well It is the greatest of all decrustifiers.. LOL

waiting for the rains to come
your old pal
rock

This may all be true, but what does it have to do with fertilizers? If I am understanding your post correctly, you would be dealing with salt build ups regardless of how you fertilize. So how does this qualify or disqualify the argument?

As I see it, it does neither.

I have been fertilizing this way since I started bonsai, and I have to admit that is was not because of some inspired insight, but out of ignorance and laziness. I always have solid fertilizer in my pots and always have liquid fert in my water/fert dispenser. My trees look great.

Thanks,
Ed

I must admit I'm a beginner when it comes to Bonsai but I do know a
thing or two when it comes to water as we own a Salt water Reef
aquarium business. etc.

There's no relationship between water quality in a salt water aquarium and water quality and fertilization in bonsai.

Corals are the equivalent of the canary in the mine when it comes to water quality in the sea or in an aquarium. They are very sensitive to very slight fluctuations in salinity, temperature or chemistry.

Plants -- bonsai -- are much less sensitive to those kinds of things. If you can drink the water you use to water your plants, they'll be fine -- with a few exceptions like ericaceous plants such as azalea and heath, etc.

I don't care how often the myth of fertilizers "burning" roots is told . . . If you are a competent grower of bonsai (i.e. you water regularly) you simply cannot burn roots -- newly cut or established roots -- by applying fertilizer in accordance with the instructions on the package that came with whatever it is you use. I suppose if someone were stupid enough to cover the surface of the soil with fresh chicken manure, the plant could be a bit unhappy for a while, but . . .

"I suppose if someone were stupid enough to cover the surface of the soil with fresh chicken manure, the plant could be a bit unhappy for a while, but . . ."

Who's using chicken manure? I read FERTILIZERS and SALT BUILDUP but must of missed something in this thread.

To others wondering about this sudden concern, as for any salt content in regular tap water, as long as you don't use unfiltered/processed ocean water, all living things need salt and water and watering as needed with tap is for most trees.

Personally, I wouldn't bother using RO water. I've filtered my own water as well for the purpose of keeping and propagating live coral in reef aquariums (soft and hard species) as RO will also strip the water of beneficial minerals useful to our trees and gardens.

This topic has become too unnecessarily focused for me - turn the hose on and water the poor things when they need it. Go on, don't be shy....