What is "tomato fertilizer"? There are dozens of different formulas under that name. Some have micronutrients, but most don't. Some people say tomato fertilizers should be higher in P than N or K. Others say they should be higher in K. Most people agree that tomatoes need calcium. I believe the ideas Al (aka Tapla) puts forth in his Fertilizing Containerized Plants posts. All plants use nutrients in close to the same ratio: 3:1:2. Since I grow my tomatoes in containers, I've been using a controlled release fertilizer with a ratio close to that and fertigate during the season with a soluble fertilizer with that ratio. I make sure my fertilizers have calcium, magnesium and trace elements. I sometimes use Tomatotone once the fruits start to form, which doesn't exactly fit the bill because it's lower in N. Reducing N at the time of flowering is one theory Al and others have talked about of how to increase yield. I always liked it when I used it in the garden, and it's easy to use without risk of burning.

There is a much narrower range between deficiency and toxicity levels when it comes to micronutrients, as opposed to macronutrients; so yes, there is considerable danger associated with excess (toxicity) levels when it comes to micronutrients. The key is not so much how much of one nutrient or another is IN the soil; rather, the issue is how much of each nutrient is soluble/available in the soil solution. Ground rock dust is just another part of the soil structure, unless it becomes mobilized into plant-accessible form. If you're supplying rock dust that is high in say P, Fe, and Mg, it will not cause plants to grow any better or taste any better unless those nutrients are deficient. One can argue the point that nutrients other than the 13 listed essentials that normally come from soil affect plant growth/taste/quality/nutrient value, but I think if we need to resort to discussing the efficacy of supplying these quaternary or quinary-level nutrients to bolster the position they are necessary, we've probably gone beyond a leap. Besides - how are we to know what they are and whether they are in the soil in the first place>? What I read of the stone to bread thing postulates so many things in the first few pages that contradict what I know about the plant sciences, that I decided it probably is going to be misleading if taken at face value. When it comes to nutrition, the simple fact is: Plants do best when ALL nutrients are available in the soil solution at adequate to luxury ranges. This means that having available more of any one nutrient than is necessary is a negative. If you pick ANY nutrient at random and imagine an excess, we can say that the excess contributes to the level of TDS/EC of the soil solution. As TDS/EC increases, the ability of the plant to absorb water and the nutrients dissolved in water decreases. That's why too much blood meal or urea is a bad thing. Too much of 'A' can also inhibit uptake of 'B', causing an antagonistic deficiency. E.G., too much Fe can cause deficiencies of Mn, too much Ca - deficiency of Mg, too much P - deficiencies of N,Fe,Z, and other micronutrients .... Getting back to the bread from stones thing, I would ask what soil is made of if not rock granules being turned to rock dust? You're right - you don't want to be running at the lower limit, that being borderline deficient, but neither do you want to be running at the other extreme, that being toxic or borderline toxic. As close as is reasonably doable, you want nutrition levels and ratios to be just like Goldilocks's last bowl of porridge. ;o) We need to lose that attitude that 'if a little is good, a little more must be better'. Balance in all things ..... Al

Definitely a pH problem with the iron uptake. People doing Aquaponics use cleated Iron since for the fish/bacteria involved in AP wants a pH closer to 7 or a bit above. The problems with vinegar and citric acid is that they break down pretty quickly allowing the pH to bounce (which is hard on plants.) The Phosphoric acid is a better choice but if you don't want to have to regularly add acid to the system, you might be better off using the softened water or rain water in your system. I had trouble with keeping my pH low enough untill I switched to collecting rain water for the hydroponics. On a side note, some media tends to bring the pH down so if you want to use something like cypress mulch or coco coir fiber, a high pH water might be good to counteract the media. Here is a link that might be useful: My Hydro Page

Dulahey, Biostimulates come in a wide variety of forumulations, ranging from vitamins, minerals and trace elements to beneficial microbes, including mycorrizhae fungi. A biostimulant is anything you use to stimulate biolglical activity in the soil. It can be something as simple as molasses or as complex as the various commercially-available products that contain many kinds of beneficial micro-organisms normally found in healthy soil. To understand why you would even need a biostimulant, you'd need to know that healthy soil is teaming with life forms at the rate of billions of them per teaspoon of soil. Organic gardening guru, Howard Garrett, said in one of his books that I read that healthy soil can have 50 billion microbes per tablespoon of soil. In order to have soil that is full of healthy life forms, you need to have soil that is roughly 25% air, 25% water, 45% minerals and the remaining 5% is humus/organic matter and is inhabited by a wide variety of beneficial microbes and life forms. This kind of soil is rich, it drains well, it holds moisture well and is full of nutrients that plants need. Unfortunately, a lot of the modern-day farming and gardening practices can harm the beneficial microbes normally found in soil. Healthy soil can have lots of soil-dwelling microorganisms including good types of bacteria and fungi, actinomycetes, beneficial nematoes, algae and protozoans. All these are, of course, invisible to the naked eye due to their small size. While these life forms perform various jobs, their main task is mineralization, meaning that they break down the organic matter in the soil, first into humus, then later into humic acid and then ultimately into the elements that plants absorb for nutrition. Soil that is low in organic matter is low in beneficial micro-organisms, and one way to fix that soil is to constantly replenish its levels of organic matter. By using biostimulants you can speed up the rate at which the soil-dwelling micro-organisms do their job, which can mean you get old, worn-out and depleted soil back into better shape more quickly. When you mix up a sterile, soil-less mix for containers, it is likely to have low levels of micro-organisms or very few of them, depending on the material you use when making your soil-less mix. Natural ways to get those micro-organisms into the soil-less mix would include the use of compost or composted manure. This is where the biostimulants come into play. If you put together a totally organic soil-less mix, you need to have plentiful micro-organisms in the soil in order to break down the organic matter into the elements for use by the plants. This is hard to achieve, especially in brand new mixes, because the process where the micro-organisms break the organic matter down into humus and then into humic acid and then into the elements takes time. Adding a biostimulant helps speed up the process. You also need to feed regularly with an organic fertilizer to keep the plants happy, and likely to help keep the microorganisms happy. Most forms of water-soluble organic fertilizers also act as biostimulants. After reading the above, you might wonder why someone would want algae, bacteria or fungi in their soil or in their soil-less mixes. Well, the algae actually produce organic matter by taking carbon dioxide from the air and combining it with energy from the sun to form new cells. The algae works with the bacteria and fungi found in soil to increase the volume of organic matter in your soil. Some forms of algae also can fix nitrogen from the air and put it into the soil. Most gardeners think of nematodes as garden pests, and that is true when you're talking about some kinds of nematodes like root knot nematodes. However, many beneficial types of nematodes live in the soil and help control soil-dwelling pests like root knot nematodes, grubs, fleas and termites. Bacteria in the soil can be helpful in many ways---some bacteria helps legumes fix nitrogen from the air in the soil and others help in the decomposition of organic matter, setting off a chain of events that improves your soil. Actinomycetes are incredibly important in your soil. They help decompose organic matter and, in the process of doing so, make many elements available to your plant roots. One of the most popular forms of biostimulants contain myccorhizae fungi. These fungi combine with plant roots (they actually grow on the plant roots) and help them grow longer and healthier. So, when you are working on developing healthy soil or in turning tired, poor old dirt into healthy soil teeming with life, biostimulant products are an important part of the process. When you put together a sterile soil-less container mix, it is not going to have all these beneficial micro-organisms if you use peat moss, but will have them if you substitute compost for some or all of the peat moss found in many recipes for making a soil-less mix. I'll find a link a page that contains some biostimulant products to give you an idea of the kinds of products I'm talking about. And, by the way, you do not have to spend a lot for biostimulants. Plain old dry molasses can be bought in 50-lb bags at some feed stores or organic gardening supply stores, and even white sugar stimulates a lot of biological activity in the soil. If you make your own compost, you'll have plenty of the benefcial micro-organisms in your compost. Some of the products that I use as biostimulants also are considered organic fertilizers, but I use them more as biostimulants than as fertilizers. This includes liquid fish emulsion, liquid seaweed, compost tea, and alfalfa tea. While they do give your plants some nutrients, the more important thing they do is stimulate biological activity in the soil. One of the easiest way to put some of the beneficial microbes in your soil is via the use of some brands of organic fertilizers that add beneficial microbes to their fertilizer blends. Espoma is the brand I use. Dawn Here is a link that might be useful: Biostimulants--a few examples can be found here