Most Frequently Asked About Supplements 101 (Part One)
by Keith Roberto
Let’s start off with the basics, since many of you may already have some experience with supplements. But before we get started, try to envision your favorite plant living in a home that it could build exactly to its liking: it rains on demand, the soil is perfectly rich or the reservoir is perfectly stocked with a tried and true nutrient solution. Some of you have also gone the CO2 route and employed top of the line lamps, too – all great investments, but nonetheless, we still hear from time to time about a supplement that can really make a difference. The purpose of this article isn’t to pitch product “A” vs. product “B”, but rather to share some insight so you’ll know what options you have and how they may or may not make your garden greener.
Humic Acid
Humates are the soluble salts of humic acids, which are derived from ancient deposits of composted plant and animal life found in what used to be a vast body of water in the Western U.S. and abroad. Over hundreds of thousands of years, heat, pressure and biological activity converted these deposits of pristine organic matter into nature’s most concentrated sources of humic acid, in the form of brown coal and lignite.
About 50 years ago, a young Soviet scientist coincidentally isolated the soluble salt of humic acid, which until her discovery had previously been impossible due to its complexity. From ordinary soil she extracted humic acids from the sample as a solution of sodium salt and then fed it to the plants. Treated plants significantly increased growth and root mass over the control plants. It was then she realized the biological activity of Humates were in fact quantifiable!
Once taken in to the plant by foliar spray or root feeding, humic acids ignite a metabolic process which leads to growth acceleration, production of powerful roots, and the assembly of special enzymes, which together increase the organism’s ability to combat stress while stocking up on vitamins, sugars, protein, and chlorophyll.
In my own case studies I’ve found the most noticeable results are richer, darker leaves, which can sometimes appear only days after initial application. It is my understanding that this color change is in part due to the improved chlorophyll activity/production, which ultimately leads to the creation of a surplus of growth energy (ATP). Another characteristic I’ve witnessed quite often is a physical hardening of the branches and leaves in plants fed with Humic Acid that also contains soluble silicon (Salicylic Acid). As you may know, Silicon is a critical component of plant cell walls. A stable supply of soluble silicon allows plants to manufacture more rigid cells, which helps protect their soft innards from external attack in addition to standing more physical abuse from the elements in the field. The availability of soluble silicon in a humic acid product has these and many more benefits to boot, such as resistance to temperature fluctuations, frost, and even drought stress.
Rigid stems and heartier tips and greener leaf blades are the norm when the proper regimen of Humic Acid is being delivered. One should also note that by adding Humic Acid to your reservoir you will lower the cohesion of water molecules so they seem to flow better through the plant, all the while bringing with them an array of micronutrients that Humic Acid’s chelating properties make possible.
The acid test: to determine the quality of Humic Acid product you use, mix a small batch in a clear glass, let it sit for an hour or two and pour off the liquid. Anything left on the bottom will never make it into solution, so if you plan to use micro drippers or sprayers, use a fine mesh filter to prevent clogs when doing so with Humic Acid Products.
Always consult with the directions on the product label for proper mixing and storage. Humic Acid has the consistency of light black motor oil and it will stain just about anything if you can’t wash it off in time.
Gibberellic Acid
Gibberellic acid is a plant hormone that can improve germination and overall plant size. In some cases it can also influence the onset of flowering, flower gender and flower size.
Gibberellic acid (GA3) is a naturally occurring plant hormone that regulates growth and triggers germination. Over 100 types of Gibberellic acids exist and each plant has many types. (GA3) is not manufactured; it’s a natural product extracted from the Gibberella fujikuroi fungus.
The main areas of (GA3) activity are to improve germination, increase the size of plants and flowers, and in some instances even manipulate the gender of flowers. I could not find any substantial research to back these claims, nor have I much experience in the field, so I’m going to leave off here. But from what friends in the field have told me time and time again, (GA3) is best used during germination, vegetating and to begin flowering, but cease and desist its use during flowering as it will rob the plant of the vital energy it requires to set forth the prized specimen you praise.
Gibberellic acid is generally sold premixed in solution, or as a dry powder which needs to be dissolved in a small amount of alcohol before being further diluted in water. Since all products are not created equal, consult with the distributor or manufacturer of your choice to determine the proper use of their product before you buy. From my own understanding, Gibberellic acid is most active within 30 days after being mixed.
To help stubborn seeds along, the generally accepted method is to prepare a (GA3) liquid solution and to soak the seeds in it for 24 hours. The (GA3) concentration should be in the range of 100-250 PPM. It operates by acting on the removal of abscisic acid, the main inhibitor inside the seed case, through the process of mechanical replacement.
OMRI is in the process of certifying many (GA3) products as we speak, so look for them soon on store shelves this summer/fall.
Ascophyllum Nodosum
Marine Plant Extract
Along with the other Organic supplements we’ve discussed here, I get a lot of inquiries about seaweed extracts, particularly those made from Ascophyllum Nodosum, which is a rock-clinging variety that grows along the frigid shorelines of Norway and Ireland.
The first records of Seaweed use dates back to about 2700 BC in China and Japan where it was used primarily as a food stuff. In the 12th century Europeans expressed an interest in using it as a top dressing in much the same way we use manure. Once costs dropped due to economies of scale, four types of seaweed came to market. Seaweed meal was fed to livestock and helped fertilize the ground they left behind. Calcified seaweed is somewhat encrusted in a coral-like state, yet it’s high in calcium and magnesium, very useful for adjusting pH. Last but not least is the seaweed extraction, which leaves the grower with a liquid material suitable for conventional irrigation techniques. Seaweed can be extracted by water extraction, alkaline extraction or micro-crushing (the purest but least effective of the four methods).
Seaweed extracts perform best when plants are exhibiting stress, whether it’s high temperature, strong light or attack by predators or pathogens. Plants treated with a seaweed extract will increase protein and carbohydrate production as well as prolong the creation of chlorophyll and the process of photosynthesis.
The hormones AUXIN, CYTOKININS and GIBBERELLIN have been found in select seaweed extracts, however, their potency will usually drop off quickly if the product isn’t used within 30 days or so.
AUXINS are known to cause cell elongation and cell division in the cambium and, in combination with cytokinins, in tissue culture (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992). Auxins stimulate differentiation of phloem and xylem, stimulate root initiation on stem cuttings, and lateral root development in tissue culture. They mediate the tropistic response of bending in response to gravity and light, delay leaf senescence and can induce fruit setting and growth in some plants, as well as promoting flowering in Bromeliads.
Here are some things to look for when testing Seaweed extracts:
- Higher yield (which I deduce would be caused by increased leaf chlorophyll). I found this most notable in tomatoes and peppers.
- Better quality produce with improved shelf life: Usually associated with improved marketable yield.
Way before our time, the planet we live on today looked a lot different. I’m not referring to cars, trains and planes, but more so about the arable land from which our ancestors literally grew our country. In 1950 the World Health Organization conducted a study by measuring how much iron was available in an 8 oz. cup of spinach. Would you believe that just 50 years later the average iron content fell from 100+ milligrams to less than 2 milligrams in the same 8 oz. serving? While some loss could be from run off, and more from over farming, the fact remains that the rich minerals once abundant at the surface are now in places your plants can’t seem to find. Supplementation using rock dust is akin to putting back to the earth what your plants take away and fertilizers fail to replace. Rock dust or stone meal, if you would prefer to call it, is a by-product of the masonry industry. Adding these pure, unadulterated minerals into your gardens and media-based hydroponics systems will make your plants feel much more at home.
The finer the rock dust you use, the better it will assimilate into your growing medium and begin to feed the microorganisms, which in turn feed your plants. A minimum of 2000 mesh material is the rule of thumb, which gives you about a .75 micron particle size of rock dust. The finer the particle size, the faster it will be assimilated by soil borne bacterium into plant-usable elements.
The most common type of rock dust in use today is that of an igneous nature - that is, rock that has been thrust to the surface from a volcano below. Basalt and Granite seem to be the most popular on the market. Basalt looks mostly pink or garnet and Granite appears grey to white.
Due to its very nature of being heavier than water, rock dust is really better suited for use by those who wish to grow in a media-based system, as the dust is still too heavy to stay in solution even in a hydroponics system that maintains a high rate of flow. In fact, without a bacterial hangout for those guys to do their job, you’re going to wind up with a lot of cloudy nutrient solution and lots of sediment that does nobody any good.
My own preference with rock dust is to use it to blend up custom potting mixes or use a broadcast spreader around my yard outside at the beginning of each season. Rock dust feeds the soil, not the plants, but as long as your soil has a good balance of beneficial biology in it, you should quickly see how effectively this treatment can stiffen up softer plants and reduce water stress and requirements. It works well enough for me to keep using it year after year and it’s literally dirt cheap!
Rock dust also helps to increase the moisture-holding capacity of soil by filling up the interstitial spaces (pores) between the grains of sand with more surface area for water to cling to using capillary action.
Always consult with the directions on the product label for proper mixing and storage. Rock dust has the consistency of talc powder and it is very easily blown around, so operate in a draft-free area when measuring.
Until next issue, this is Keith Roberto, Author of How-To Hydroponics, with another round of tips and tricks in the garden.