The 12 days of Crop Nutrients

Day 2

Welcome to our second day of the crop nutrients post. Hopefully you caught our first day – where we focused on phosphorus. In the traditional Christmas carol, the second day is two turtle doves. Since I don’t have any clever alliteration ideas for this one, I am going to talk about a secondary nutrient: calcium.


Calcium (Ca)

Calcium is a secondary plant nutrient that stimulates root and leaf development, activates several plant enzymes, and is required by nitrogen-fixing bacteria. In the soil, calcium indirectly influences yield by reducing soil acidity. It also helps improve root growth conditions, molybdenum availability, and uptake of other nutrients. In the soil, calcium indirectly influences yield by reducing soil acidity, which in turn lowers the solubility and toxicity of manganese, copper, and aluminum.

Alfalfa calcium deficiency comparison. (Left has deficiency, right does not)

Calcium is the third most important element in a plant. And, calcium is the fifth most abundant element on the planet. It makes sense that traditionally, growers don’t apply much calcium, because they assume the plant will get what they need from the soil. But, soil calcium is usually found in a form that is not easily taken up by plants.


Calcium deficiency in an apple

As an example, in an apple tree, the leaves, new shoots, and fruit all take calcium. The nutrient will be found in the tissues and the root, but the fruit cannot compete with the other parts of the plant. Hence why the fruit often doesn’t get enough calcium. That is why calcium deficiencies are evidenced on the fruit, rather than the rest of the tree. In apples, a calcium deficiency causes a disorder known as bitter pit. Bitter pit is a physiological breakdown of the cell walls in the fruit that occur below the skin of the fruit. For that reason, when scouting for calcium deficiencies in fruit trees, it is important to test the fruit, rather than relying solely on leaf or soil tests. Signs of calcium deficiency common in all crops include abnormal dark green foliage, premature shedding of blossoms and buds, and weakened stems.


Further problems with the calcium levels in the plant, and therefore in the fruit, are often caused by changes in the weather. In high temperature, low humidity conditions, for example, transpiration will increase dramatically, causing the plant to use more water. In irrigated crops, if watering has not been well scheduled, even soils with good levels of calcium can have problems in the fruit caused by calcium deficiency, such as blossom-end rot in tomatoes. This is the time when we need a fast calcium fertilizer that can be applied by foliar.


Common symptoms of calcium deficiency:

  • Death of growing points
  • Abnormal dark green foliage
    Example of calcium deficiency in lettuce
  • Premature shedding of blossoms and buds
  • Weakened stems
  • Tip burn of young leaves (primarily in vegetable crops)
    Calcium deficiency in corn
  • Water soaked, discolored areas on fruits
    Canola with a calcium deficiency

Increase Alfalfa Tonnage and Digestibility

Daniel Peterson, CCA, SSp

Field Agronomy Manager

As the order for the potash, phosphate, sulfur, and micronutrients is submitted, what are the reasons, or goals, for applying that fertilizer? Why fertilize alfalfa? Some reasons would likely include increasing or maintaining yield or avoiding “mining” the soil.

There is another reason that AgroLiquid customers are discovering, and it ties in with the industry’s understanding that the digestibility of a ration’s forage component has a large impact on a cow’s milk production. That is why cut timing is carefully managed, weather conditions are closely monitored, weeds and insects are controlled, and the bunks are filled and packed quickly. Recently the dairy industry is also paying more attention to alfalfa fiber digestibility.

For several years dairy customers have been saying that AgroLiquid fertilizers were doing something to their forages that went beyond more tons. They were getting more tons and more milk/cow/day when the AgroLiquid treated alfalfa was fed compared to their conventionally fertilized alfalfa. Then, last year, these personal accounts were put to the test when Poplar Farms Sales and Service near Manitowoc, WI, in cooperation with their Dairyland Seeds representative, decided to split north/south an alfalfa variety plot which was planted east/west. The field split compared conventional dry potash top-dressed against AgroLiquid’s Sure-K applied foliar at 6”. They tested each variety on each treatment for quality and digestibility in addition to dry matter yield. The results were significant, with markedly better Neutral Detergent Fiber Digestibility (NDFD), protein, Relative Feed Quality (RFQ), milk/ton and milk/acre on the Sure-K side. AgroLiquid Field Agronomy Manager for the upper Midwest, Dan Peterson, took note of these results and conducted an additional 11 alfalfa field and test plot trials across Michigan, Wisconsin, and Minnesota during 2016. He discovered the results were indeed repeatable, with all 11 trials showing positive results for the AgroLiquid treatments versus the conventional fertilizer treatments. This level of repeatability is unusual in agronomic testing, and provides strong evidence that AgroLiquid foliar products are doing something unique in the plant, something that other liquid foliar and dry fertilizers are not doing.

The 11 field splits and test plots were across several different conventional dry and foliar treatments and were compared side-by-side to various AgroLiquid foliar treatments. The average of the results across all fields and cuttings showed remarkable results from the AgroLiquid treatments:

  • 37.3% more dry matter/acre.
  • 2.6 more lbs of milk/cow/day (per NDFD).
  • Over 20% faster digestion rate (per the Dynamic NDF kd).
  • 5% more protein.
  • 40.5% more milk/acre.

The trials were from new seeding through 4th year stands, across different cuttings, soil types, soil fertility levels, and geographies. The AgroLiquid treatments were compared to conventional dry fertilizers, top-dress manure, and competing foliar products. Although the results varied, in every trial the AgroLiquid treatment resulted in a large ROI over the other treatments. In addition, in every trial the AgroLiquid treated side reached maturity between cuttings three to five days quicker than the conventional fertilizer or manure side of the fields. This may allow an additional cutting for the season. Dairy producers who participated in these trials noted not only the faster regrowth but more and larger leaves and less of the typical leaf yellowing below the canopy.

The question is how do AgroLiquid’s plant nutrient products achieve these remarkable tonnage and digestibility improvements in alfalfa? The answer is likely their unique Flavonol Polymer TechnologyTM. The flavonol organic polymer facilitates better nutrient uptake and utilization within the plants with less metabolic energy expended. Review the individual alfalfa trials at

lucerne alfalfa
The beautiful backdrop of Lucerne (alfalfa)