This is a great article on watering and feeding with different mediums.


walter-pall-bonsai.blogspot.com/2010/06/...atering-english.html

great article its about time somebody cleared this up. I have been in so many arguments on what is the best soil mix

Well, I have read it and most is good. Soil is a choice we all make according to the requirements of the trees and where we live. I will use that which has been good for my trees for a long time, and I have no intention or need to change.
Watering also is to everyones situation not one size catch all.
As for "feeding" we do not feed trees we add fertiliser.

LOL feeding or fertilizing? (semantics).
The thing I love about this article is that it reminds people what I have always known, and that is Akadama, and similar mediums are really just hydroponics. Anyone with experience in hydroponics knows that every watering has nutrients in the solution. You never water hydroponics without feeding. That is why hydroponics has higher yields and faster growth than organic mixes. Organic mixes retain salt and NPK. This creates a build up that must be washed away with water. Because clay and rock mediums retain very little salt and NPK, you can safely feed your plants as much as 1200PPMs per watering without any problems.
I feed my trees twice a week without anything but good results. Here is what I use.

1st feeding of the week.
Maxsea 16-16-16 base nutrient. 1/3 strength
Pro Tekt Silica 0-0-3 Silica
GH Floralicious/humic acid and seaweed extract
Molasses 1 Tablespoon per 2.5 gallons of feed.

2nd feeding
Fish emulsion 5-1-1 1/3 strength
Compost tea
Hygrozyme
GH Rapid Start root hormone
Molasses 1 tablespoon per 2.5 gallons of feed.

Once a month I add
by hand, a dash of epson salt to each pot.

If a tree is stressed or is transplanted I add
Vitamin B
Superthrive
GH Rapid Start rooting hormone

This is my regimen, and I follow it almost to a T, all of it is chelated and fast acting.

Great article to read! I can't believe I have shortchanged my trees by feeding at 1/4 strength once a week. Looks like I can expect some explosive growth next year when I start using this method. I have just been using basic Miracle Gro liquid fertilizer.

Did I read that right that he used both? Liquid on top of granulated fertilizer?

There is a difference and it is not semantics. The tree does not and cannot absorb the chemicals added to the soil. The tree uses them to convert to useable substances, it is called photosynthesis.
Akadama is not hydroponics, hydroponics has the roots in water.
The problem with these articles is that as I said before it may work for the person who uses it, but that does not mean it is suitable for all. I do not.agree that you cannot overwater with Akadama, if I watered as he suggests my trees would float away.Also White Pines in particular and other species too do not like being too wet.

I would assume your soil blend holds much more water than what he uses. Walter says that if it is free flowing enough, it would be almost impossible to over-water.

I pretty much agree with anything he says. He is a legend in my book. I would take his advice over practically anybody else's.

I use Akadama, and it is not quite as simple as what he says. There are different sizes of pot for a start, so a shallow one will dry out quicker that a deeper one. As I said before what works for one is not nesessarily going to work for all. Temperatures and humidity also have an effect on the amount of water is retained in the soil. If the weather is cool and damp or wet then it is not a good idea to keep watering is it?
I made the mistake some years ago of changing the soil I was using because someone told me it was the best thing ever. It was the worst thing I had done, and the following year I had to repot again to get them out of the soil mix. So, I will not change just because someone says so. I will stick to what works for me. If you wish to do what he does that is up to you.

Hear hear! Glad to have read it, and I also thought the same paralell of hydroponics being very similar. My pre bonsai trees love being fed everday (currently with a full strength 8-16-36 chemical fertalizer).

But wait Stiple, is that a ficus in hydroponics, and in fired clay hydroton at that? But wait hydroton cant be almost identical to akadama, because akadama isn't hydroponics. Yes it's true that hydroponics is not just for deep water culture as m5eaygeoff suggested, infact hydroponics is growing a plant in any growing medium that is non organic and fed every watering. Here is a definition:

hy·dro·pon·ics
ˌhīdrəˈpäniks/
noun
1.the process of growing plants in sand, gravel, or liquid, with added nutrients but without soil.

That sure sounds an awful lot like akadama? Hmmmmmm..........so maybe it really is basically hydroponics. But I wouldn't know, even though I was a professional hydroponic grower for years. So now that we have that is straitened out, it's on to a word I have never heard up until m5eaygeoff brought it up, photosynthesis.
M5eaygeoff you claim that in quotes

"The tree does not and cannot absorb the chemicals added to the soil. The tree uses them to convert to useable substances, it is called photosynthesis."

But that is entirely untrue, the plant has to absorb these minerals, not chemicals as you put it, in order to use them for carbohydrate production. In fact, the most effective way for this absorption to happen is through the correct ph of the water, which depending on the plant is roughly 6.0. Tap water can range from 7 which is neutral to an alkaline state upwards of 8.5. Anything out of the ideal range and the plant, or tree can not effectively absorb all the nutrients provided with efficiency.
So although you say fertilizer and I say feeding we both know what the other is talking about and saying the same thing two different ways, so yes semantics.