I was invited to discuss nutrient supplementation on another popular gardening forum very recently. The reply I left is rather appropriate to your wonderings, so I'll post what I left there: If what I leave you with finds you with additional questions - please ask. I get asked this question frequently, or a variation like: "I want to feed my plants the best - what's best & how often should I feed?". Most people queried, would look right past the question and hand you a box or direct you to the fertilizer section of a plant store for "plant food". Actually, you cannot feed your plants. Food provides energy - fertilizer does not. Plants manufacture their own food during the process of photosynthesis when the pigment chlorophyll traps the energy of the sun in a molecule of carbon dioxide and water. The result of this miraculous reaction, without which the earth would be uninhabitable, is a molecule of glucose - sugar - a carbohydrate - photosynthate. The molecule acts just like a battery, storing energy from the sun that can be translocated to all living plant parts for immediate use, or stored in living cells - roots, leaves, and cambium for later use. In order for a plant to make and use food efficiently, certain elements need to be available to the plant. In fertile garden soil, it is likely, even probable that that the nutrients will be available in a usable concentration. In container culture, it is a virtual certainty that we will have to accept the responsibility for providing nutrients in usable concentrations for the term of the planting if we are to expect plants to grow at or near their potential genetic vigor. The three main elements or compounds that are needed for plant metabolism are nitrates, phosphates, and potassium (NPK), and they represent the bulk of ingredients in balanced fertilizers. We term these ingredients macro-nutrients, sometimes referred to as "the majors". Also included in the macro-nutrient category, but necessary in lower concentrations are magnesium, calcium and sulfur. Rounding out the list of nutrients needed to keep plants healthy are the micro-nutrients, or "the minors". These nutrients include iron, boron, zinc, copper, manganese, molybdenum, chlorine, cobalt, and nickel. Please note that some of the minor elements, or micro-nutrients are required in such minute amounts that deficiencies are rare in garden soils, but more common in container media. For that reason, it is good practice to insure that you use a fertilizer that is complete, including the minors. If the minor nutrients are not listed on the fertilizer package, and youre unsure that your soil contains an adequate supply, an excellent way of providing the minors while furnishing major nutrients is to use a granular soluble or insoluble product (e.g, STEM or Micromax). Organic fish and/or seaweed emulsions as part of your supplementation program can also be effective, but here I'll concentrate on the major elements. Now that we've have seen that fertilizer is not plant food, but a way of delivering some of the raw materials or building blocks that plants need to make their own food and keep their systems orderly, I'll briefly say that it is important that we insure the soils we use contain adequate/appropriate volumes of air and water so as to make nutrient uptake possible and efficient, but that is another subject I won't dwell on today. You can probably use a schedule or timetable to fertilize plants & have them be reasonably happy, but I use a different approach. If you do choose to fertilize on a regular schedule, it makes no sense to continue to fertilize when plants are quiescent due to chill, heat, or other unfavorable cultural conditions, Under these conditions, you might extend the preset intervals. Plants need more nutrients when robust and actively growing and less when they are "coasting". I use a two-pronged approach to my fertilizing. The first thing I do is note leaf color of older leaves. N is a very mobile nutrient in plants. When it is deficient, plants "rob" it from older leaves to use in the production of new vegetative growth. So, when I see a lightening of leaves toward a lighter green or yellow, especially older leaves, and I'm sure that other cultural conditions are what the plant requires for good vitality, it indicates to me a need for supplemental nutrients. A simplification of how I fertilize is: I attempt to get a higher percentage of N to foliage plants or those that are being grown for a reason other than blooms or fruit. Highly nitrogenous fertilizers support the plant during the growth of leaves and foliage. For flowering/fruiting plants, the phosphatic portion of fertilizers aid flower/fruit production, so I'll usually include the intermittent use of a fertilizer with higher percentage of P. Potassic compounds (K) stimulate the growth of roots and are included in adequate percentage in all complete fertilizers I use. I use both chemical and organic fertilizers. As noted, but worth repeating, I determine the need for fertilization by leaf color. When leaves lighten and fertilizer is needed, I mix a recommended full strength solution of 20-20-20 soluble granular fertilizer and add a full strength solution of 5-1-1 fish emulsion in the same mix. This mix, I'll apply to foliage plants & plantings that are not dependent on blooms for their beauty. This is pretty much my standard for these plantings. For blooming plants, I'll use the same 20-20-20 fertilizer with a 2-3-1 fish emulsion included - UNLESS leaf color is good. If leaf color is good - I'll substitute a bloom-inducing, soluble formulation like 10-52-10 or 15-30-15 and still use the 2-3-1 emulsion. In all cases, I'll apply these solutions to well-hydrated plants growing in moist or damp soil, thoroughly saturating the entire volume of soil in the container. I prefer the reliability and immediate action of the chemical soluble fertilizers for results, but understand the wont of some to remain organic. Generally speaking, organic fertilizers do release nutrients over a fairly long period, but there is a potential and considerable drawback in depending solely on them. They may very well not release enough nutrients to give the plant what it needs, when it needs it for best vitality. Organic fertilizers depend on soil organisms to break them down into elements the plant can assimilate, so most of them are effective only when soil is moist and soil temperature is warm enough for the soil organisms to be active. This soil organism population is a boom/bust proposition in container soils due to the extreme variables of temperature, moisture and pH. Nutrients in chemical form are immediately available for plant use and exhibit no dependency on soil biotic activity for availability. Plants do not care whether their elemental building blocks are provided in chemical or organic form.color> Additionally, practices that promote high population numbers of soil organisms that feed on organic particulates hastens soil structural collapse, which is certainly counter-productive to your need for an extended-life soil. When I think of soils that must last long term, I immediately consider the percentages of organic:inorganic componants. If I want a soil to last several years, I'll use something with more than 2/3 inorganic parts, like Turface, pumice, perlite, Soil Perfector, etc., and only 1/10 - 1/3 organic parts - usually fir or pine bark. For plantings of 1-2 years, I'll use a mix of primarily bark, peat, perlite. Well, I certainly never intended to go on so long; and I know I bored some into leaving before they got this far, but for those that made it to the end, I hope my thoughts were clear enough to provide some insight. Al Fassezke

JOSH: Good to know about the avocado, I'm betting that it actually loves being flooded that often, given how they love drainage and they're grown commercially on hills. I didn't bare root my first avocado (a sir prize). It was in a decomposed granite mix that drained really well, so I just knocked a bunch of dirt off and stuck it in. It's been growing pretty well, but I'm worried I might want to bare root it to a more consistent mix. My Jan Boyce was bare rooted and nearly died, lost all but one sad leaf and half its branch tips turned black. But now it's flushing out all new growth. The Mexicola and Lamb Hass laughed at being bare rooted and acted like nothing happened, Mexicola especially, the thing is indestructible, and the lamb hass kept holding fruit (that I've since removed). I also have a Hass and Kona Sarwil that complained a little but were otherwise fine with bare rooting. And all this was right before the crazy heat wave and fire storm down here. NIL: WOW, fantastic resource. I didn't know about Nutricote before but their product line is impressive -- I need to make a field trip to Yamada. It's the one in Gardena, right? SHAZAAM: Interesting ideas, the bags are definitely big on wicking and air exchange. None of my bags are touching the earth, they're all on my patio, driveway or elsewhere. I imagine if I put them on bare dirt, they'd act like a raised bed and one could get away with almost any mix. In fact, if I were doing that, I'd do a raised bed mix to encourage more worms and things to till the bed (I did that last year with a peat-mix in 10 and 15 gal bags and it worked great, tons of worms and growth). I just calculated how many gallons of 5-1-1 I've made. It's around 350 -- 20 15-gal bags and the rest 7 and 3 gal. I wanted to stick the basic recipe before going off the reservation, but, yes, let's compare notes. The more I read about DE, the more I think it's a great addition.

This upcoming year, I am probably going to overdo it again based on my excitement and desire to try different things. However, here is my tentative plan: March: I am going to get soil tests in two places: 1) where my grass is going great 2) the two spots where the grass is shaky April 1: I am going with a chemical preemergent. I just feel like I have to break the weed cycle for a year to give the grass a chance to fill in. I will also drop some corn meal gluten at that time. I will spray my first round of compost tea. May 1: I am going to go with some corn meal, not corn meal gluten, since I have had some fungus problems. I will continue with a light spray of compost tea. I am obsessed with getting the right bacteria/fungi situation going on my lawn - hence the compost tea and corn meal. June 1: Once again, I am going with a light sprinkling of corn meal as well as some compost tea. August 15: Alfalfa September 1: Compost, Overseed, Milorganite. October 1: Milorganite or soy bean meal, along with some compost tea. November 15: Cockadoodledoodoo chicken fertilizer. As you can see, I am going with a few different things because not only do I find this all fun, but also I am not sure what will - or won't - work. Here are my reasons: 1) corn meal gluten: They say it takes a couple years before it truly works. So, while I am working it into the soil, I am going to give it one last shot of synthetic preemergent. 2) corn meal: I have a hunch that I have some fungus issues. 3) Alfalfa: I am doing this for the phosphorus that will be needed two weeks later for the overseeding. 4) Milorganite: I like Milorganite. I have liked the results thus far. 5) Cockadoodledoodoo: My uncle uses it, and his house is the first in his neighborhood to green up. Also, the organic company that services my neighborhood uses something like it exclusively (all applications), and their lawns are always as green as the chemically treated ones.

I agree with Violet. I too, am a health professional and there are more people(especially young people) developing more cancer and chonic diseases. And there are plenty of studies out there that show environmental links. Also studies done on the nutrient content of food shows that during the last 50 years, our veggies and fruit have become less nutrient packed. The studies indicate that this is due to the fact that the N_P_K are being returned to the soil in adequate amounts by chemical fertilizers, just not all the micro nutrients that we need for healthy bodies(the plants do not necessarily need them to grow). We need more types of nutrients to grow than plants. It is true that the nutrients in chemical fertilizers are just as effective as those in organics. Its just that it is not complete. In organic gardening, before any nutrient in the soil is used by the plant, it must be available in a form the plant can absorb. This is done by bacterial action. The organic nutrients are first used by microscopic organisms and the waste that is produced feeds our plants. Adding chemicals kills not only earthworms, it kills the microorganisms that allow us to garden organically. This is how "dead soil" develops. I am sure that an occasional use of chemicals is not going to destroy your soil, but my thinking is why at all if you are going organic. I know that there are many organic gardeners out there that insist that only compost is needed to garden organically, and I am sure plants grow just fine with that. But compost is a soil amendment, not a fertilizer. Everytime I harvest vegetables or fruits from my raised beds,I add a compost and a tiny bit of alfafa meal(nitrogen), rock phosphate(Phosphorous) and Kelp meal(potassium and trace elements). I've been doing this for quite a few years now and my yields improved, my plants are larger, and I have no trouble with diseases or insects. I learned from not only what I have read, but what I do, that healthy soil and growing organically makes a difference. Hope some of this information helps.