Miracles of Balanced Plant Nutrition

BY NOEL GARCIA CCA/COO Senior Consultant, TPS Lab

Most growers typically take an early spring soil tests and then apply a pre-plant fertilizer to last for the entire season (sometimes supplement ing Nitrogen, later on). They base this application on the recommendations of the soil report and assume that the one application will supply the crop’s nutritional requirements for the remainder of the season.

There are several problems with this approach:

• Much can happen to your fertilizer after it hits the ground, making it unavailable to the crop: • Your native soil chemistry can rapidly tie-up fertilizer components into chemical compounds that the plant is unable to absorb. • Irrigation water high in mineral salts not only changes your soil’s chemistry and damages its structure, but also neutralizes plant-ab sorbability of many fertilizers by changing their chemistries into plantunavailable compounds. Water quality is critical if you fertigate.”What’s In Your Water Becomes Part Of Your Soil.”™

• Chemical interactions between the fertilizer components themselves can render them unavailable to the plant. • Loss due to the weather – leaching due to heavy rain, high soil temperatures, etc. • Volatilization of Nitrogen into the atmosphere. A pre-season soil test provides a starting point for determining what the soil needs to get the crop off to a good start. But the soil may have several issues that need to be dealt with in a coordinated manner to ensure the critical early part of the growing season is managed for the best results.

• Crop nutritional demands typically vary widely throughout the grow ing season. The wrong fertilizer applied in incorrect amounts at the wrong time is simply wasted – often leaching into nearby waterways. But worse – your crop ends up malnourished, resulting in yields and quality often far below your crop’s potential. Worse yet, crop malnour ishment can stress crops, making them vulnerable to diseases and insects requiring insecticides and fungicides, more water, making susceptible to drought, heat, and cold (late frosts). “Nature always eats the weakest with bugs and disease.” So, you end up spending a whole lot more to get a lot less.

• Standard soil testing methods used (Mehlich III and others) by most labs, measure nutrient compounds that are both plant-available and unavailable. Both are counted in subsequent recommendations to you. (Sidebar: Reports on some soils often show Phosphorus, Potassium, Calcium or Magnesium as being consistently adequate or high.) This means that the lab has to estimate (guess) what is available to your crop based upon its experience with your soil and general fertilization rates based on crop nutrition standards published in the early 1950s. an extraction method that mimics roots in the soil; on the other hand, makes calibration possible. And the problem with relying on 70-yearold standards is that they do not account for new varieties, discoveries in plant nutrition, and deteriorated soil quality (high salts, low organic matter content, and collapsed structure).

Now you can understand why your soil test reports show pretty much the same results and recommendations, year-after-year, even as your yields and quality stay flat or decline while your costs go up.

Balanced and Complete Plant Nutrition Goes Way Beyond N-P-K

Nineteen elements have been identified as being necessary to plants – the number of which depends upon the plant. It’s only recently that the importance of micronutrients (Iron, Copper, Zinc, and Manganese) to plant health and quality have started being talked about. With ongoing research, discoveries are being made almost daily about the importance of heretofore ignored trace elements – most recently, SILICON. A few years back, Silicon was acknowledged as being “ben eficial” to mostly small grains, as it helps prevent lodging by hardening cell walls. However, ongoing research reveals that the benefits to very many crops and soils go far beyond that: • Chewing and sucking insects, and disease are discouraged by hard cell walls. • Research suggests that a thin physical barrier forms on root hairs, thus discouraging nematodes and disease. • Improves nutrient uptake • Improves drought resistance • Improves soil permeability • Many, many other benefits – and more to be discovered

But there’s more: A nutritionally balanced crop is better able to with stand stress caused by adverse growing conditions (cold or hot, dark or bright, wet or dry, etc., weather). And – as we’ve experienced in the field, maturation time can be shortened by as much as three weeks!

When we encounter a field suffering from disease or insect problems, the first thing we should ask is what’s the nutritional status of the crop.

Correcting nutritional problems alone won’t necessarily fix a field already in distress. Still, it is crucial to address underline nutritional deficiencies to better the odds of eliminating disease and insect pressures.

More Than Just The Elements

There are a variety of products such as biological inoculants, sugars, hormones, humates, organic acids, which are game-changers and need to be an integral part of your fertility program, especially biologi cal inoculants.

Biological inoculants in both soil and plant – do a lot: • Converts plant-unavailable soil nutrients into plant-available

• Controls soil and plant pathogens • Conditions soil, regenerating structure • Helps remediate salty soil physical and nutritional qualities that release plant-available nutrients during the process (Good levels of humus are essential for thriving plants) • And a whole lot more

Soil microbiology is an exciting part of today’s agricultural research with newly-discovered benefits and characteristics happening often.

Sugars stimulate biological activity and reduce the excessive vegeta tive growth of plants caused by too much Nitrogen. Hormones and Organic Acids are essential components of accelerat ing plant development – and are especially useful when dealing with crop damage (due to hail, etc.) and assist in establishing crops during cold springs. We often see that these products, in addition to balanced nutrition, can restore a hailed-out crop within two or three weeks and rapidly (usually, in one season) turn worn-out fields from disasters into successes!

Plant Tests

Plant tests provide you with feedback about your crop’s nutritional condition. It is impossible to know about how much of your expensive fertilizer has been absorbed by the crop and what the crop’s immediate needs are. Plant tests are tissue tests from leaves, petioles (leaf stems - plant sap), or the whole plant. What leaves/petioles are sampled, the stage of growth, when they are collected and the nutritional standards used are critical to how lab results are interpreted and reported. The primary differences between labs are how the results are interpreted and what recommendations are made.

Leaf or Petiole? Very generally speaking, leaves contain the historic nutrient record of the plant. Petioles contain the nutrients flowing within the plant at the moment the sample is taken.

When should you test?

Many farmers only act after there are visual signs of damage in the field. The problem is, by the time problems are visible, yields and quality have already been lost. At this point, it’s more about damage control – to hopefully prevent further loss. Frequent plant testing allows you to correct nutritional problems seven to 21 days before they can be seen. Testing is done at specific stages of crop development, ranging from weekly or biweekly for fast-growing or high-value crops and less often for others. It is critical, however, that your lab knows what the nutrient content is supposed to be at the stage of growth when the samples are taken.

More To It Than Nitrogen

Some farmers are only interested in Nitrogen content. Even though N-compound tests are cheap and N is undoubtedly essential, N-only tests are a waste of money and effort because they don’t account for other critical nutrients. Consider “von Liebig’s Law of the Minimum.”

Does Your Plant Test Include Essential Nutrients?

We’ve already seen that there are a lot of nutrients required for proper and balanced plant nutrition – only a few of which have been men tioned here. For a complete picture of your crop’s nutritional status, you need to know about secondary nutrients, micronutrients, and trace elements. Plants have different and unique nutritional requirements, especially for trace elements.

Plant Tests Are The Cornerstone

…for maximizing your crop’s potential and solving serious crop problems – especially when dealing with diseases and insects. Your lab should be able to provide you with recommendations for each stage of plant development for a successful season-long fertilization program. Providing your crop with balanced nutrition throughout the season is the most crucial factor in-field performance – and your bottom-line!

What To Take Away From This Paper:

• If your lab’s soil reports and recommendations are pretty much the same, year-after-year, there’s something wrong. • If you follow your lab’s plant test recommendations and things still aren’t working well, there’s something wrong. • If you have a disease or insect problem, there’s something wrong. • If your yields and quality are flat, mediocre, or are generally declin ing, there’s something wrong. • If the quality of your soil isn’t improving with each year, there’s something wrong. • The Devil is always in the details – especially the smallest ones.