MSU and K-Lite?

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wjs2nd

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I have a few questions about the two and didn't want to hijack anyone's thread (I saw that Ray's thread is about K-Lite reviews and I have never used K-Lite). Plus, I hope this becomes informitive for others. Their is so much experience with these two fertilizers and I don't have any.

1. I read some discussion about continual dose feeding. What dose do you suggest with MSU and K-Lite? It seemed no higher then 70ppm N was recommended. What is the easiest way to measure this/figure this out? I know easiest isn't always best, but not all of us have TDS meters. I have RO water. Can I use 1/4 teaspoon per gallon, or should it be even less?

2. With the discussion about deficiencies, has anyone thought about rotating between MSU and K-Lite? Could this cause an imbalance? (I know none of the deficiencies/issues seem to actually be from K-Lite).

3. From what I could read, you don't need to add calcium if your using K-Lite? Is that because of how it is balanced?

4. If you continually feed, what do you do during winter: every other watering, or stop feeding altogether? I have a few orchids where I'm not suppose to feed them in the winter.

These are all the questions I can think of. If anyone else has questions please post them.
 
First understand that the K-Lite formula was actually derived from the MSU RO.

Both are designed for continuous feeding. The concentration and frequency of application both play roles in the mass of food you end up providing.

If you have a calculator handy, you can do the following:

At 1 teaspoon per gallon, each %N on the label provides 12.5 ppm N in the final solution. Therefore, if you're shooting for 50 ppm N, 50/12.5=4, so take whatever fertilizer you have and divide 4 by the %N to determine the teaspoons per gallon to use. If you're shooting for 75 ppm N, divide 6 (75/12.5) by that label percentage.

Alternating/rotating the two would be roughly equivalent to blending the two, giving you a formula somewhere in between. We are intentionally suppressing the P & K, so that would defeat the purpose of the experiment.

For most plants, the fertilizer has plenty of calcium in it. There may be some species that are particularly demanding of it, so a bit of crushed oyster shell on top of the medium may be warranted for them. Personally, I don't bother.

If you have plants needing a rest period, simply withhold fertilizer altogether.
 
About the pitting amendments, I have always believed that the potting amendments like oyster shell and limestone chips were to keep PH in the pot at an acceptable range. 6-7 seems to be a common ground where most things are available to the plants. If you grow in S/H or some other way where you PH isn't going to drop drastically then you would never need to add them. But if you grow in bark and are not right on top of your repotting schedule then the PH drops as the bark degrades. I can see it in my plants. I was never under the impression that oyster shells would dissolve fast enough to provide the plants with an adequate amount of calcium. Dolomite power may do a little better at providing some calcium. When I first started growing I had alot of conversations with growers about this and the concensus seemed to be the same oyster shell for PH adjustment, cal nitrate for calcium. So I dont see why you would not need to add it with k-lite because the ph is still going to drop.
 
Ray: thanks for the explanations! I finally feel like I understand how to measure %N for feeding (at 12.5 N per teaspoon, 4 teaspoons will give you 50 ppm N per gallon of water). It is good to know that both are meant for continual feeding. I guess I should have clarified that I didn't mean alternating between the two every watering, but more spacing the change out (few months MSU, few months K-Lite). Of course, this was also before I knew K-Lite was derived from MSU.
 
every feeding has a light fertilizer solution instead of just giving the plant a periodic dose
 
About the pitting amendments, I have always believed that the potting amendments like oyster shell and limestone chips were to keep PH in the pot at an acceptable range. 6-7 seems to be a common ground where most things are available to the plants. If you grow in S/H or some other way where you PH isn't going to drop drastically then you would never need to add them. But if you grow in bark and are not right on top of your repotting schedule then the PH drops as the bark degrades. I can see it in my plants. I was never under the impression that oyster shells would dissolve fast enough to provide the plants with an adequate amount of calcium. Dolomite power may do a little better at providing some calcium. When I first started growing I had alot of conversations with growers about this and the concensus seemed to be the same oyster shell for PH adjustment, cal nitrate for calcium. So I dont see why you would not need to add it with k-lite because the ph is still going to drop.

The material in oyster shell or lime/stone is calcium carbonate. As it dissociates (in acidic soils) it releases calcium and bicarbonate. The bicarbonate is the chemical that buffers the pH (as alkalinity), but the calcium either gets picked up or flushed away.

Soil pH (kind of a big environmental black box concept) controls the uptake of lots of different materials, bicarbonate ion (also available from baking soda or soda ash) is directly part of the uptake of nitrogen (specifically ammonia). So that's why K lite (98% or so nitrogen from nitrate) should not use lots of calcareous potting ammendments.

In the absence of soil ammendments, soil pH can be controled by use of increasing percentage of inorganic media in the mix, and watering frequency.

One of the reasons soil goes acidic under high ammonia fertilization rates, is that nitrificatious bacteria use alkalinity to convert ammonia to nitrate. In the process of loosing alkalinity, pH drops.

So pH drop can be just another symptom of overfeeding since significant nitrification in the potting mix means you are feeding the bacteria in the potting mix instead of the plant.
 
Thanks Rick. I'm guessing this process will increase the breaking-down of your medium. This in-turn increase the nitrification process which increase your medium break-down (a vicious cycle).
 
So if you feed at a low rate will the ph stay constant for an infinite number of years with no drop at all? Even in bark that has turned to dirt.
Have you checked this, let bark turn to dirt while only fertilizing at a low rate and checked the PH the periodically throughout the process?
 
So if you feed at a low rate will the ph stay constant for an infinite number of years with no drop at all? Even in bark that has turned to dirt.
Have you checked this, let bark turn to dirt while only fertilizing at a low rate and checked the PH the periodically throughout the process?

I'll never admit to infinite:wink:

But there are also organic acids that come out of bark and moss products that lower pH.

But working with a fresh batch of sphagnum moss in a single basket I did find over the coarse of a year, that the organic acids in the moss that were forcing the pH to about 6.0 initially, flushed out. So by the time the moss was pretty well broken down and crumbling, I was getting pH a bit higher than 7.0 in flush water (esentially the assumed organic acids had been washed away and not effecting pour through pH).

I work in the waste water biz, which focuses on nitrifciation. It's pretty amazing how much a small amount of these bacteria can change the environment. Bill Argo (in consideration of the development of the "rain water and well water" forms of MSU also considered the nitrification effect in developing the 2 formulations.
 
Ray- can you address continuous feeding using K-lite and: (1) hydrogen peroxide and (2) seaweed extract?
Hydrogen peroxide? Essentially no nutrient value whatsoever, and probably has little-to-no effect on the nutrients.

Seaweed? Probably some trace elements, but I use it for the auxins to stimulate growth, not as a nutritional supplement.
 
Ray: thanks for the explanations! I finally feel like I understand how to measure %N for feeding (at 12.5 N per teaspoon, 4 teaspoons will give you 50 ppm N per gallon of water). It is good to know that both are meant for continual feeding. I guess I should have clarified that I didn't mean alternating between the two every watering, but more spacing the change out (few months MSU, few months K-Lite). Of course, this was also before I knew K-Lite was derived from MSU.

4 tsp? that sounds like a lot.
 
4 tsp? that sounds like a lot.

I agree, 4 tsp. to attain 50 ppm can't be right. For MSU RO, to get 125 ppm N use .768 teaspoon (That is directly from the Greencare label for MSU RO). If K-lite is based on the same formula, the proportion should be the same.
 
Missed 1 part of the math.

12.5 ppm of N for EACH 1% of N on the label.

So if the fert mix is 12% N (look at the NPK label on the bottle) then each teaspon yields 150 ppm of N.

So if shooting for 50ppm final then 50/150 = 1/3 of a Tsp.
 
Okay, I thought that was high but I don't have a lot of experience with this.
So if grow more 20-10-20 has 20% N
Then, 1 teaspoon yields 200 ppm of N
So a 1/4 teaspoon would be 50 ppm of N
I planning on getting MSU and am trying to figure out the math first.

Ray's math makes sence to me now. I had some trouble following the wording. Math is easier for me to follow with more of an exsample based problem.
 
Well if the 1tsp = 12.5ppm holds up for your fert then that's actually 250 ppm per tsp. and a 1/4 tsp is 62.5 ppm (close enough to 50).

However, volume of fert (tsp) doesn't always track with weight.

So you might expect to be off by 20% or more measuring different solids by volume rather than weight.

That's because the NPK values are % based on weight of the different ingredients.

For instance a 20-10-20 fert has 20% N by weight so every 100 grams of fert has 20 grams of N 10 grams of P (actually phosphate) and 20 grams of K (actuall potash). For one thing notice that the sum of those 3 doesn't add up to 100 grams.

Then which takes up more space? a pound of lead shot or a pound of feathers? Different solids have different densities, so a Tsp of feathers is going to have a lot less mass of product than a Tsp of lead shot.

Fortunately fertilizer salts aren't as extreme as feathers and lead shot for density differences so you can usually get away with tsp measurements and be close enough.
 

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