Liquid Fertilizer

[rockm]

"Rockm, I think Eric Shrader was right earlier who stated that both Miracle Gro and Dyna Gro are salts. They can build up no matter what concentration you use. Leading to leaf burn, white stuff growing up your trunk, and I think, but am not sure on this one, is affects the soil pH. Organics do not. But I agree with everything you said: N-P-K is N-P-K no matter what fert. you use. But the salt factor is something that imo, is not good."

This is a needless worry and something the "organic" proponents always say to disparage "chemical" ferts use. They certainly can build up (to varying degrees) but the danger (if any real danger) is mostly cosmetic if you're using appropriate bonsai soil and reading directions. Salt build up is overblown if you using soil that drains adequately and are applying in correct amounts.

I aggressively fertilize many of my trees. I have done so for over a decade. I have had no problem with leaf burn or white stuff on trunks. I've had stains on pots, but organics, when used in quantity, can do that too.

There is a real danger with organic pellets too. Use them long enough and they will clog the heck out of the drainage in your soil. I had to blast about two inches of dissolved cakes out of my large live oak's pot last spring.

PS, if you're trying to measure pH in bonsai soil, good luck. It's grainy composition and tricky water retention properties can make such readings very hard to get, much less rely on.

 

[JudyB]

Rockm, I think Eric Shrader was right earlier who stated that both Miracle Gro and Dyna Gro are salts. They can build up no matter what concentration you use. Leading to leaf burn, white stuff growing up your trunk, and I think, but am not sure on this one, is affects the soil pH. Organics do not. But I agree with everything you said: N-P-K is N-P-K no matter what fert. you use. But the salt factor is something that imo, is not good.

This is something I've been concerned with, as I have had issues in the past using Miracle gro, I've gotten salt buildup on pots and trunk bases.( One very nice unglazed pot, I just can't get the salt stains out of, even after scrubbing with vinegar water...) Switching to Dyna-gro has helped in that respect as it's urea free, and has less build up potential.

But I'm still concerned about this, as when I run out of collected water, or need to use the sprinkler system to water that I'll continue to get too many salts in the plant. I'm on a well, and use a water softener. I water with rainwater as often as possible.

So I've been trying to work out a fert strategy for next year. I can't use cakes as raccoons tear them up to eat them, so I've been thinking about using green dream mixed in when repotting, and trying a dilute fish emulsion in conjunction with the dyna-gro I use now. Most of my trees are in development stages, I only have one or two, that I'd consider "finished" or thereabouts. I've been looking for something for more aggressive feeding. Does this seem like a reasonable approach to try?

 

[rockm]

"I'm on a well, and use a water softener."

What kind of water softener? Some softeners ADD SALT to the water to "soften" it...
http://en.wikipedia.org/wiki/Water_softener
This may be a big contributing factor...

 

[JudyB]

It is like that, but I use a potassium based pellet instead of the salt.

 

[rockm]

If I remember my high school chemistry correctly, Potassium is classified as a salt. It is also one of the primary ingredients in fertilizer. You might be doubling down on the Potassium when you fertilize your trees...

 

[JudyB]

From what I can glean, potassium has less sodium, although it's very similar in its makeup to salt.

I am able MOST of the time to use collected rainwater. It's only for the couple of weeks a year I'm away or a week when I'm super busy. And during those times, I'm basically not using any fert at all.
The salts that were building up on the trunks and pot, happened when I was using Miracle - gro as primary fert. I've not seen it since I switched, and scrubbed it off the trees and the pots. Could be that I was doing more tap watering at that time, and I've just forgotten that part.

What do you think of using those three ferts (green dream mixed in, dilute fish emul.,&dyna-gro) together as an aggressive program?

 

[rockm]

They'd work, but it's not really an "agressive" program. I fertilize with Miracle Grow at full strength every two weeks in the spring. I have also used Bio Gold pellets at the same time. I've also used Dynagrow, but found it wasn't really worth the expense. I've used only tap water for the last 20 years or so on all my trees. Have never had an issue with it, but my tap water comes from the Potomac River, not a well.

FWIW, things are never picture perfect all the time for your trees. Lime build up (which might be what you're seeing, not salt build-up per se) is part of the deal in growing trees out. I get rid of lime build up on ceramic pots by burying them for the winter in composted pine bark mulch, which is acidic and dissolves the stuff away.

 

[Bill S]

Judy in this issue a salt is not table salt(NaCl). although I can't remember if a chem salt has sodium.

Fish and seaweed emulsions are on the low end when it comes to NPK, you would most likely not notice much difference if you used it at the same time. Not sure what dynagrow consists of so I can't answer that part.

 

[treebeard55]

A bit of chemistry, if I may ...

In chemistry, a "salt" is a compound made up of a metal and a non-metal. Table salt is also a salt in the chemical sense: it is a compound of sodium (a metal) and chlorine (non-metal.) Its chemical name is sodium chloride. There is also potassium chloride, a compound made up of potassium (metal) and chlorine (non-metal,) potassium iodide, and thousands -- tens of thousands -- of others.

Unless I'm mighty much mistaken, most fertilizers deliver nutrients -- at least some of them -- in the form of salts; the plants break the salts down to get at the nutrients in them. (Our bodies do the same thing.)

No offense, but to say "salts" are bad for plants is too simplistic. Some salts are good for plants, some are harmful.

And anything is harmful in excess. There's even such a thing as oxygen poisoning!

 

[treebeard55]

... You wait till you start seeing fall leaf color changes before changing over. ...

Chris, I'd better add that I'm still learning to judge when to make the switch. I suggest getting hold of some others in your area, too, and see what they say.

 

[Klytus]

Should one lime ones Bonsai if the municipal water is soft,what about those poor souls whose tap water arrives undrinkable from the desalination plant?

 

[Bill S]

reverse osmosis comes to mind. They make all kinds of filters.

 

[JudyB]

I think I'm confused about what salt is what. I read that potassium salt was lower in sodium than table salt, but I didn't know that they were 2 different things. I'm no chemist for sure. Just looking for a better and safe feeding for next year. Wish I could do cubes....

 

[Eric Schrader]

I am a chemist, at least by schooling. Really - bachelor's degree. I also work on chemistry textbooks for a living - hence the photo of a beaker pouring water on a tree for my avatar. Here are a few thoughts:

Sodium - Na - bad for plants. It occurs in city tap water because it is not bad for humans in dilute concentrations (My water has 65 parts per million) It is an ion and it competes with Potassium (K) in a plant's metabolism and prevents plants from uptaking water properly in high enough concentrations. Plants absorb water by osmosis - the movement of water across a cell membrane from an area of low salt concentration to an area of higher salt concentration (not Na alone but other salts as well.). No fertilizer will contain sodium as it is essentially a poison for plants.

Potassium - used by plants for growth - and hence in fertilizers. It exists as an ion very similar to to sodium; if you look at a periodic table it is directly below Sodium which means that it is chemically nearly identical in behavior (nearly identical - but different enough to be important obviously.)

Other things that are common in city water are Calcium (as an ion), Iron and Magnesium. The total content of these ions is what is a measure of how "hard" water is.

Unfortunately it's not even that simple when it comes to water chemistry and trees. Municipal water is typically at a pH of 7.5-8.5 which means that there are more positive ions (H, Na, Mg, K, Ca) in the water than negative ions (Cl, OH, and others). (In pH 7.0 is neutral) Trees generally prefer a soil/water pH of around 6 which means that they want more negative ions than positive ones. The difference in the pH affects the uptake of nutrients almost more than the presence of the nutrients themselves.

Adding salt-based fertilizer can affect the pH of the the soil and water and thus negatively impact the ability of the plants to uptake nutrients, and in high enough concentrations to uptake water - which is what causes leaf burn. When a salt (think of table salt) is dissolved in water it's crystal structure of alternating ions breaks up and the ions are in solution which is good for nutrient uptake in plants if the right types of ions are at the proper concentration and the other ions in the water don't interfere with them.

I would recommend to anyone that is having problems growing trees they check their municipal water quality report to see what the pH of their water is and what ions are generally present. You can also test the pH from your tap with litmus paper or pH paper or an electronic meter. When I lived in San Francisco I had no complaints about the water but after moving it was a whole different story. After comparing the two reports I noted that the concentration of sodium and calcium were nearly three times higher here in SoCal than in SF. The other differences were less remarkable.

I recommend the use of both organic fertilizer and mineral-derived fertilizer - not one or the other, but both. But more importantly than the fertilizer is to make sure that your plant can absorb it properly. Check the pH of your water and the Na/Mg/Ca content. Hard water problems can generally all be eliminated with an RO system which removes nearly all the ions from the water and lowers the pH in the process. The down side is that the systems waste water and that water without any minerals is not so good....thus adding something like Dyna-Gro to every bit of water in a low concentration adds back the needed micronutrients without adding back the ones that are detrimental.

Hope that all makes sense and that I didn't mis-type anything.

 

[Jason]

I'd get something that contains nitrogen, phosphorus, and potassium.....and then worry about the semantics (while your fertilizing).

 

[monza]

I think for us newbs the clarity once studied should be obvious. Feed your trees feed them regularly.
Trees don't care.
I can post three experts opinions (or more don't know why I picked three) all with different feeding routines.
Argue Walters feeding practices? No, not me he's like a tree god. Brent Watson solid info. Rockm, always solid true facts. There's three I could go on and on...

Me, I take all the experts and mash them together for my climate. I live in a cold and harsh enviroment.
My fall temps are actually hotter then summer temps (f'd up) then Bam winter and hard frost and freezing. Six months of winter. So I know some think trees are smart, but why not hold back the bacon (n) and get them ready for a winter that is coming? Bacon at the buffet who can resist?

 

[fore]

That's a good idea Steve. Thanks for the suggestion.

 

[Oliver Muscio]

As another chemist (professional), I will second Eric's post--he has it right on. As an educator, I can't resist a bit of correction on what Treebeard wrote. Although most salts do consist of a metal ion, and a non-metal ion, a better definition is that a salt is the ionic product of the reaction of a base with an acid. For example, sodium hydroxide, Na(+)OH(-) and hydrochoric acid, H(+)Cl(-) react to give water, H20 and sodium chloride, Na(+)Cl(-). The base, and therefore the resulting salt, need not contain a metal. For example the base ammonia (NH3) reacts with nitric acid (HNO3) to give the common fertilizer ammonium nitrate NH4(+) NO3(-), a salt.

I know this is eye-glazing stuff: I apologize, I just couldn't help myself!
Oliver

 

[CamdenJim]

rockm wrote "However, it can be a good idea to switch off between two prepared ferts in a summer because mixes tend to have different levels of trace elements."

First of all, I'm a total newbie at bonsai. I use Orchid Bloom Booster on Bougainvilleas (not bonsai) to encourage blooming, and it's the trace elements that do the job.

Would the same trace elements be of any help with our bonsai?

 

[jk_lewis]

ALL plants need trace elements. NPK is NOT enough (which is why I add trace elements to all bottles of fish emulsion which has almost none).

Under US law, the label on all fertilizers MUST list all of the ingredients and their percentages. Many other countries follow suit.

Please do not overcomplicate fertilizing of bonsai. It is not an arcane dark art. Use a formulated houseplant fertilizer that contains NPK and trace elements and you will be fine. No need to mix and match, though it doesn't hurt so long as what you use has the trace elements -- iron. copper, manganese, magnesium, calcium, etc.