Tomato Plant Nutrient Uptake?

[BajaMitch]

I have been dabbling for 3 years at growing tomatoes in the ground, in a large planter box, and recently in self-watering containers. I have decided to get serious about it. So...I have been doing some studying (a lot of studying, actually)...and I have discovered that we all have been guessing at this avocation instead of working from a position of knowledge. I want to grow tomatoes in a self-watering 5 gallon container and I need to know the answer to my question.

Bottom line, what we all need to know is:

"How much (by weight) of each of the 6 macronutrients does a tomato plant uptake over its life span, specifically N, P, K,C a, Mg, S and what is their relative proportion, by weight, to each other?"

I will not and do not buy the argument for not answering the question is that there are too many variables, many of which I have enumerated below. I believe that the discourse in this forum and others reflects a great deal of energy and time expended in wild ungrounded guessing while missing the real question that should be answered with regard to tomato plant nutrients/fertilization. Answer the question and we all could greatly improve our results and cut out a great deal of waste both in money and in materials. And, I know that the answer is already a known thing.

There are sixteen total nutrients, but the real focus should be the abovementioned six as H and O are already in the atmosphere and C is plentiful enough in organic substrates. The micronutrients are easy enough to supply with fertilizers such as liquid kelp, fish emulsion and others without the need to be very specific in quantities.

We need to know this information in terms of grams for each of these six macronutrients. And, it would be nice to know the different uptake amounts for the different phases of growth.

Now, I do know that the answer should be in the form of a defined range of grams for each of the nutrients. The answer will vary from cultivar to cultivar, and, there will probably be variances related to location/climate/time of year planted. But, the answer should not vary much with regard to the varying sizes of containers. I do expect that there may be variances between certain cultivars, but I believe that the answer in terms of nutrient ranges will be very similar for the broad majority of cultivars, especially when compared to other vegetables and fruits.

Let me stress that the question is a botanical question of the nutrient uptake of the tomato plant and not how much nutrient to add to the substrate. How much to add to the substrate will depend on the size of the container, specific potting mix used, how the nutrients are administered (mixed in, a strip, periodic feeding, fertigation method, etc.)

Also, the answer should give us a good "proportional" profile, that is, for a given tomato plant, what is the proportion of N to P, K, Ca, Mg, and S.

I would be happy to know the uptake range for two specific common and representative cultivars. That would be a good starting point.

I know that info is out there in the world and there are those that actually know it in specific detail, but "those people" are obviously not among us because that info is just not "out there" in any forum or article that I have ever come across.

Another variable is the size of the container. The uptake capacity of a plant, in general, could be thought of as independent of the container size, but it is generally acknowledged that a bigger container yields bigger plants, therefore, more plant uptake. But to know the general "uptake capacity" of a given plant gives the grower/hobbyist a great point of reference grounded in measurable objective reality from which to scale up or down the nutrients administered. Also, I would hypothesize that, for the most part, the total nutrient uptake for a larger growing plant in a larger container Vs. a smaller container, the relative proportion would remain the same. So, you still would have a good point of reference to scale up or down with the size of the container.

Another variable with the size of the container is that the necessary concentration of nutrient per cubic inch will vary: larger container the lower the concentration per cubic inch of container substrate. This evident by comparing nutrient concentrations between the EarthTainer and the EarthBox.

The best that I could find were studies that were done on entire crops and the answer to the nutrient uptake question is addressed in terms of hundreds of pounds of nutrients for the crop. Sometimes these studies disclose the amount of tomato crop yield in tons and sometimes they even may disclose the tonnage of left over plant stalks, but the info to get specific on a per plant basis is just not out there.

I took one study and did some calculation wherein I used some substantial assumptions (rendering my take as a mere educated "guess"). One of many problems in my assessment is that the study gave the weight of NPK and Ca, Mg, and no S...and...it was not specific enough to let me know if the values/weight for P and K were its atomic weight or whether it was the weight of P2O5 or K2O.

Nevertheless, I am going with my assessment for next year's self-watering containers and applying the nutrients in varying measured quantities and multiples of quantities, using specific cultivars, using my assessment of nutrient uptake per plant in grams as my experimental point of reference, and measuring the weight of each of the macro nutrients by the gram per container. I will be experimenting with other criterion such as air holes/no air holes on the sides of the containers lined with landscape material, administering the nutrients in a strip vs mixed in the substrate vs periodic feeding over the life of the plant.

My goal is to come up with an optimum specific substrate mix for a 5 gallon self-watering container (next year I am going with 3 parts Kellogg premium potting mix, 1 part sphagnum peat, 1 part perlite), specific quantities of nutrient added per container in the form of grams per macro nutrient all at the lowest cost possible. It doesn't make sense to me to grow my own at costs that exceed the cost of tomatoes at the market.

Again, the real question that we should be focusing on is "What is the nutrient uptake of a tomato plant in grams per macro nutrient on the average and what is the relative proportion of each of the six macronutrients to each other per plant in grams"?

[AKmark]

I am not sure if you are asking, or explaining, but at any rate this is a pretty good link I have posted before, I hope it helps with the coined " real question." I have a bunch of these links if this does not suffice.

http://www.haifa-group.com/files/Gui...ato/Tomato.pdf

[BajaMitch]

Thank you for taking the time to provide a comment. I have read that PDF before. It is a good one.

The info in that PDF refers to rates over time, but doesn't provide actual uptake totals per plant. The graphs that could have some value are 3.1, figure 5, 6 and 7. I don't know how to read Figure 5 as it is in grams/plant, but it describes rates of uptake and I don't know how to derive or calculate a total of nutrient uptake for one plant for each macronutrient based on that graph (leaves out S). Figure 6 is in Kg per hectare per day and it relates to rates of uptake over time, so it would be uncertain as to how to derive a macronutrient uptake per plant over its life in grams from this graph. Also it leaves out Ca, Mg, and S. Figure 7 and 8 are very interesting but they are not accompanied by the weight of tomatoes produced or the plant itself (also leaves out S). However 7 & 8 can be used if you weigh a plant yourself and keep track of the weight of the yield of fruit yourself. The question there, however is that 7 & 8 are in % of macronutrient by weight, but you would have to know the amount of water contained in the plant and in the fruit. That requires other sources of info. Now, we are faced with putting detached sources of info together and estimating the calculated results.

Table 7 has some really good info on speculating about comparative amounts of NPK uptake. Very valuable. It would be great if the PDF article had provided the same info on Ca, Mg, and S. However, it is actually telling us what they provided as nutrients rather than claiming actual uptake.

This article is very similar to much of the info out there regarding plant uptake, often talking about what, how and how much they fertilize, but not actually disclosing any findings on actual uptake.

Remember that whatever nutrients are provided to the soil or grow media, only a portion is uptaken by the plant and fruit and the rest is left in the grow media.

The study that I used provided me the amount they added to the soil, the amount that wound in the plant and the amount that wound up in the fruit by nutrient weight. They actually harvested the plant and dehydrated it and chemically analyzed the dried remains. The same for the fruit. And, if you did the calculation, you could derive the amount of nutrient left in the soil. I want more info on other cultivars by other researchers so that I can compare and corroborate the results.

It's a great article. Loved it when I read it before and would be good reading for everyone interested in growing tomatoes.

The question on the ground is "How many grams of each of the six macronutrients does a tomato plant uptake over its life time?" Somebody out there knows; I am sure of it.

AKmark, if you have other articles or references to more info that would get me closer to the answer to "the question", that would be fantastic.

[AKmark]

I will add this, every variety is a little different, and some will produce over long periods of time, while others peter out. I also have noticed that many hybrids seem to require less fertilizer.
I try not to read to much into this, I use HG fertilizer and add Calcium and Magnesium Sulfate, as well as a K boost at first truss harvest, and a couple of weeks after that. I run my mixture at 1600-1800 ppm, and it is just awesome, I just can't imagine upping anything much more.
I am doing a few experiments this year and will elaborate if it pans out, and I am sure it will if the research I have been doing has lead me in the right direction.
I will suggest some new products after I try them, I have a very knowledgeable grower, who works between Alaska and Hawaii, he is very confident in some suggestions.
I was looking for this, you may like this too, thought I would edit it in.
http://www.spectrumanalytic.com/supp...ium_basics.htm

[BajaMitch]

Thanks, AK, for the excellent article on Potassium.

Regarding "The Question", if I could corroborate my assessment of a tomato plants uptake, I could more accurately administer nutrients to my mix for a 5 gallon self-watering container for tomatoes.

If my assessment is any where near correct, a lot of things that I have read about what many people have done to fertilize their plants seems way off, chemically speaking. For example, it seems to me that many people are putting way too much N in their mix, and others are administering disproportionate amounts of K, Ca, and Mg completely ignoring the effects that too much of one of those nutrients completely crowds out the other two. For example, putting two cups of Dolomite or straight Calcium Carbonate in one container is an affront to the concept of balance between K, Ca and Mg. But, it is also axiomatic that one cannot argue with results.

Furthermore, it seems that others are spending a ton of money on really expensive potting mixes such as ProMix when all they really have to do is use a decent but low costing potting mix like Premium Potting Mix by Kellogg and an appropriate amount of this mix with the right amount of peat and perlite to adequately and sufficiently support wicking and Cation Exchange Capacity. Even if they do get great results, it could be cheaper to grow two smaller containers with the mix I suggest and get a total larger yield from two lower costing setups that one expensive attempt.

When it comes to adding fertilizer nutrients, I have spreadsheets that are programmed with the % by weight (in grams) of each macronutrient for each amendment so that I can calculate the exact quantity for each macronutrient (in grams) supplied by a given quantity of the fertilizer/amendment.

All I need at this point is to corroborate my findings with other well founded uptake info and then I should be able to estimate with reasonable accuracy how much to put into the soil/mix.

The only substantive variable at that point will be to get a good handle on the concentration per cubic inch for different sizes of containers. With a good starting point, that is, having actual on point info on macronutrient uptake for a tomato plant, determining the varying concentrations of the mix will be relatively easy and quick.

[pecker88]

Originally Posted by BajaMitch

Thanks, AK, for the excellent article on Potassium.

Regarding "The Question", if I could corroborate my assessment of a tomato plants uptake, I could more accurately administer nutrients to my mix for a 5 gallon self-watering container for tomatoes.

If my assessment is any where near correct, a lot of things that I have read about what many people have done to fertilize their plants seems way off, chemically speaking. For example, it seems to me that many people are putting way too much N in their mix, and others are administering disproportionate amounts of K, Ca, and Mg completely ignoring the effects that too much of one of those nutrients completely crowds out the other two. For example, putting two cups of Dolomite or straight Calcium Carbonate in one container is an affront to the concept of balance between K, Ca and Mg. But, it is also axiomatic that one cannot argue with results.

Furthermore, it seems that others are spending a ton of money on really expensive potting mixes such as ProMix when all they really have to do is use a decent but low costing potting mix like Premium Potting Mix by Kellogg and an appropriate amount of this mix with the right amount of peat and perlite to adequately and sufficiently support wicking and Cation Exchange Capacity. Even if they do get great results, it could be cheaper to grow two smaller containers with the mix I suggest and get a total larger yield from two lower costing setups that one expensive attempt.

When it comes to adding fertilizer nutrients, I have spreadsheets that are programmed with the % by weight (in grams) of each macronutrient for each amendment so that I can calculate the exact quantity for each macronutrient (in grams) supplied by a given quantity of the fertilizer/amendment.

All I need at this point is to corroborate my findings with other well founded uptake info and then I should be able to estimate with reasonable accuracy how much to put into the soil/mix.

The only substantive variable at that point will be to get a good handle on the concentration per cubic inch for different sizes of containers. With a good starting point, that is, having actual on point info on macronutrient uptake for a tomato plant, determining the varying concentrations of the mix will be relatively easy and quick.

Like AKmark mentioned above, there is a lot of variability in nutrient tolerance between tomato varieties. Even though the plant can uptake quantity x of nitrogen, it might not tolerate it.

I had a very simple experiment a month ago.
-2 identical Krakty hydroponic setups, both containing the same concentration of 4-18-38, calcium nitrate, mag. sulfate.
-2 identical grow bags, same exact soil mix (Fox Farm Ocean Forest) in each bag
-started 2 Better Bush VFN Hybrid seeds; promix BX
-started 2 Bush Beefsteak seeds; promix BX
-at about 2 weeks, 1 each seedling went into Krakty setup
-at about 3 weeks, 1 each seedling went into Soil setup
-all plants were under the same lights; a total of 800w HPS

Results:
-Better Bush VFN Hybrid in Krakty was dead in 2 weeks; toasted brown.
-Better Bush VFN Hybrid in Soil is still living and has 1 small tomato; the entire plant is toasted brown
-Bush Beefsteak in both Krakty and Soil is doing great; probably 6 or so tomatoes on each plant

Conclusion:
The variability in nutrient tolerance is high. In my case, I'm estimating the Hybrid could only handle 1/3 or less of the nutrients that the Bush Beefsteak could. Maybe I'm wrong, but your analysis would have to be conducted separately for each variety of tomato plant.

[BajaMitch]

Great test, Pecker88.

Certainly does show a difference in toleration. I am sure that differing tomato plant varieties will not only have different nutrient tolerances but will also have differing uptakes; noting that uptake and tolerance are two different things themselves. It is important to make sure that tolerance and uptake are not to be confused in assessing results, however.

Your experiment definitely illustrated tolerance variances, but not sure how it reflects on a better understanding of actual uptake. Could be that the excess in the grow media environment was the problem causing some chemical interaction problems (such as a crowding out effect or as an inhibitor to other nutrients) more than an uptake excess (if that is even possible) for that given variety.

Since my intent is to derive a mix and nutrients that are optimal in terms of optimizing cost and yield, applied plant nutrient excesses due to tolerance should be eliminated as a factor when getting closer to the actual uptake capacity of a given plant.

I agree with your conclusion that, for the most part, my specific experiment efforts will and should be limited to specific cultivars to eliminate variability in uptake and to a lesser degree, nutrient tolerances between plant varieties. There will be enough other variables to work with for sure.

If a grower provides the optimal quantity of macronutrients, that is, hypothetically, the exact amount of macronutrients added to the grow media that permits and provides and makes available to the plant the exact amount of macronutrients that matches the plant's exact uptake requirements, no more no less, the plant will thrive at its optimal best. It creates an optimal physical grow media environment for the plant to uptake optimal amounts. Adding slightly more than the plant needs doesn't help (like taking more vitamins than the human body needs or can use) and actually reduces the plants optimal health to some degree depending on the excess, as your experiment showed. Adding less nutrient definitely does hurt because it results in a deficiency.

Theoretically, the object is to try to find the exact uptake of macronutrients. That will provide the best point of reference for adding nutrients to the grow media. Exact, as a practical matter, is not all that necessary, and with normal resources, probably not possible, but close would be a great step forward.

I know that info is out there and someone somewhere knows the answer, albeit an approximate one.

[AKmark]

You are correct if I follow you concerning antagonism between nutrients when one gets out of balance. The one I pay most attention too is K, and when it's high you should see Magnesium deficiency, always in older leaves. However, K has a tolerant toxicity level that I know of. (I am not sure I worded that as good as I can)
One thing you can play with is surfactants, Silicic acid, this will change all of your nutrient uptake, I suggest reading up on this, looking at the process where Silicon becomes available to the plant, and why it works.
Here's another link
http://www.smart-fertilizer.com/arti...zer-solubility

Could you not measure out your nutrients for the year, then test upper end levels to find upper tolerance/ by number of plants, then you get how much was taken up? I think you are looking at the whole process backwards. I simply start with a reference, then creep everything in a direction, it is what it is in the end. If they need more or less I adjust, then I have found the plants uptake level.
We also should note that much of the info we use is over 50 years old, I seriously doubt we are going to reinvent the wheel, but instead should be focused on improved management overall, these guys have done the painful brain work for us, for the most part.

[BajaMitch]

What you write makes good sense, AK. Not having all the resources in the world makes it necessary to do trial and error no matter how much info one has. As I mentioned before, I analyzed a certain study, did a bunch of calculations, and derived an average over two different cultivars for the specific macronutrient uptake in grams for one tomato plant. I am using that as my starting point and point of reference for next year's experiments. Then, analyzing the EarthBox and EarthTainer together with other peoples representation of their specific use of fertilizers and grow media for their containers, I derived comparative data on concentrations of macronutrients (in grams) per gallon of grow media.

This concentration info together with my own determination of a tomato plant uptake will help me formulate how much nutrient to add to the grow media per 5 gallon container. At that point, it will be trial and error, but, I will have a reasoned and substantiated point of reference from which to establish the varying and closely measured nutrient quantities.

The trick is to combine the various fertilizers in just the right quantities so that I can arrive at the stated gram-levels of each of the 6 macronutrients per container. That's tricky business, but I can get really close. I have a wide array of nutrients: ammonium sulfate, TomatoTone, Citrus and Avocado Food, calcium carbonate, sulfur, Epsom Salt, composted chicken manure, compost with horse manure, fish emulsion, 17-17-17, bone meal, potassium nitrate, Kellogg premium potting mix, perlite, sphagnum peat moss, and Sul Po Mag. Looking to add a couple of others to this arsenal. Also, looking into mycorrhizal inoculum.

Most all of these nutrients state their official content in % by weight of NPK and other macro and micro nutrients. I had to make some educated guesses on a few items. The compost with horse manure gives me their annual chemical analysis report. While my analysis will not be exact with each and every given fertilizer since they are known or represented to contain nutrients for which they do not report specific %'s, I am comfortable overall.

Had a bad crop this last season as I was winging it without any real data. Set up 4 self-watering containers late in the season (July 1st) after ripping out all my other failed plants. With these 4 containers I had one control which was straight potting mix only with a tablespoon of bone meal and a tablespoon of Epsom salt thrown in the hole where the seedling went. The others had various mixes and various quantities of nutrients, but the control did the best by far. By August 1st, I had derived my guess at plant uptake and I periodically fed the control container since Aug 1st and completed making sure that the container had the equivalent of my calculated guess at plant uptake by Nov 1st and nothing more.

As of this date, the control is doing the best of the four in spite of probably under feeding the plant. None of the plants are robust as I live in a canyon and lose the sun early, plus it has been cold and getting colder since Holloween. I live in Southern California. The overnight temps have been below 55 F for the last month and a half and often nearing 41 F; its been cloudy off and on as well. The plants are still alive and two of them have been flowering like crazy in spite of the weather. The control and one other plant have generated over six growing tomatoes - remarkable. Even though one could say that the plants are not looking particularly robust and that their rate of maturation is about 3 times slower than if they had been planted in early May as opposed to July 1st, I think they are holding on valiantly and I have gathered a little good and important empirical info.

Not enough bees in the area to help fertilize the plants, so I have been flicking and shaking the flowers and occasionally buzzing with an electric tooth brush and it is really paying off as there are many more apparent buds coming along. To my amazement, one tomato is actually ripening and turning red...and that isn't even on the control plant.

Next year should be much, much better...says me.

[AKmark]

I have a friend up the road who uses a wide variety of fertilizer sources, kind of like the list you mentioned. I brought to his attention that he cannot precisely measure some ingredients when they are added. What we did was measure his run-off, and his ph. His runoff was only 600ppm, and that explained why his plants looked like crap. I highly suggest buying a TDS meter, and follow directions of your chosen fertilizer. If your ph is good 6.3, I promise you will be ok, and will not have to think as hard. I own a commercial greenhouse, and trust me, I have heard some good ones.

[Worth1]

""I have discovered that we all have been guessing at this avocation instead of working from a position of knowledge.""

""I believe that the discourse in this forum and others reflects a great deal of energy and time expended in wild ungrounded guessing while missing the real question that should be answered with regard to tomato plant nutrients/fertilization.""

I guess we are all idiots.

There is one thing I think I have not seen in your posts but maybe I missed it.
Nowhere have I seen any mention of Soil pH.
Without this being correct and being maintained correct you can kiss all of the other stuff goodbye.
Keep this around 6.5
If the pH of the soil fluctuates so will the uptake of the nutrients.
The type of water alone you use can make this happen.
The type of soil you grow in can have an effect on the uptake of nutrients.
The microbes in the soil can have an effect.
The source of the nutrients can have an effect.
As well as the temperature of the soil.

But of course I am just guessing as well as the rest of the people here and not working from a position of knowledge.


Worth

[BajaMitch]

Great suggestion AK, I have been thinking about such a meter. That meter would be helpful, certainly with a top watering container approach where I have read that the run off should be around 15% of the water supplied. Monitoring that run off would enhance the measurement of what is retained by the grow media and give good clues to the uptake. For self-watering containers, the meter could be used an samples taken from the reservoir.

If you or others could recommend a make and model that does well, would be greatly appreciated.

Worth, you make good points, no question about that. Water analysis is readily available from the utilities that serve the area. Done that. Also, the pH range for tomatoes is well known by most all of us and is readily available and there are known ways to control it. Most experts say that maintaining the pH within a recommended lenient general range is usually quite enough. The pH affects uptake not because of the specific uptake characteristic of the given plant itself, but because it affects the chemical environment that exists in your substrate around the plant roots and the interference with cation exchange capacity of the substrate (and the cation exchange process) itself. Different substrates can have wildly different cation exchange capacities ("CEC")...and that chemical fact is also a known commodity. The temp of the soil slows down or speeds up chemical reactions, just how much is difficult to know, but there are published recommended ranges on those temp ranges as well. The planter can measure the exact temps and in some instance do something about it, especially with containers. Also, microbes affect the environment around the roots and in the soil as it processes the different chemical forms of nutrients into more plant readily available forms over time. I think that is why ProMix BX is so effective as a substrate.

Most all of the factors that you mentioned are really important and certainly affect the "nutrient availability" and the "root environment" to the plant and most are known, measureable and for the most part controllable items, but what is not known is the actual innate, intrinsic, inherent uptake of the plant. For example, a potato famine once reduced the food intake of the people in Ireland, but in and of itself, says nothing about how much nutrients are required by an individual Irish man or woman. A nutritionist or a physician recommending a diet needs to know what the human body requires, then knowing what specific foods to eat will follow...in that order of importance, I think.

[AKmark]

The 15 percent may be correct in soiless, but when you have compost items in the mix the runoff will be much higher than the 15 percent of the water going in, if we are talking continuous feed fertilizer.

At any rate, I enjoy your thoughts, you certainly will succeed, you seem to be one who does not read the first and last sentence of a book.

BTW, if all fails, grab some Miracle Grow and follow the directions. LOL HAHAHAHHA. We poke at it, but myself and I am sure many others, have had good luck with it. LOL

Like Worth said, all of us questions our brilliance. lol

[Worth1]

I think the only way you will even come close to finding out your question is to somehow take every tomato and all of the plant and get them analyzed as to what they contain on an Atomic level.

I think you are asking just how much of everything the plants needs throughout its life if I am not mistaking.
What I had to do the fix things up was to experiment.
First I had to get the pH right and to find out why it was fluctuating.
Then it dawned on me it was the city water.
I found heavy calcium deposits in my pressure canner on the soil and around my drip lines.
Now I could have scraped this stuff up and put in in a flame to prove it but didn't.
If I had of it would have been a nice brick red color.

Worth

[BajaMitch]

AK, I had to laugh along with you as I know the logical fall back position is MG or ProMix. If I can't crack this nut, MG or ProMix is what I am looking at. But, believe me, I am not going to give up easily...having too much fun fighting the odds at this point.

Worth, when I looked up the water content here, I was shocked to find out how much Ca is in the water. My calculations show that four months of irrigation for one plant in a 5 gallon self-watering container may add up to 14 grams of Ca. That's a lot.

This brings me to another very relevant issue that has been heavy on my mind but almost never talked about and that is how much or how little the added plant nutrients migrate through the soil/mix in order to reach the roots or to be reached by the roots.

I know enough about chemistry and physics to know that the different nutrients and the different forms of each nutrient will probably travel through the substrate at differing rates, and some may not migrate much at all. There is a little bit of info out there on some nutrients as to how much or how little they migrate through the grow media, but not much info. I think that info is going to be more elusive than the answer to "The Question".

The variables are not limited to the different forms of each macronutrient, but further complicated by the differing substances used to make up the substrate itself. This nutrient migration issue will greatly affect how much nutrient/fertilizer is added to the grow media and how it is added, i.e., pulverized, dissolved in water, pelletized, in a fert strip or mixed in with the grow media or periodically fed throughout the growing season.

BTW Worth, the study that I based my assessment of a given tomato plant's macronutrient uptake (except for sulfur) did exactly what you mentioned. That is, the study disclosed how much fertilizer/nutrient they put in the soil, desiccated the plant stalks and chemically analyzed them for all its elemental content and disclosed the weights of those elements, and desiccated the tomato produced and chemically analyzed those and disclosed the elemental content, all for two different cultivars of tomato. So far, that one study has been the only study that I have come across that did that kind of analysis with disclosure.

At the end of the day and in the final analysis, my goal is to come up with the optimum simple and inexpensive grow media/potting mix recipe and efficient use of the correct minimum amount of low cost nutrients that will generate reliable crop quantity with repeatable success using self-watering containers all with a minimal amount of plant maintenance. If I can get reliable repeated success with a reliable 75% of optimal plant yield, I will consider it a smashing success. If I can get better than 75%, that will be considered a freebe bonus. So far, I think 75% can be done realistically...says me.