MegaCal vs. SurCal+: The Importance of Calcium

MegaCal vs. SurCal+ and the Importance of Calcium

All plants require a combination of macro and micro nutrients. Macronutrients can then be broken down into primary and secondary nutrients. Primary nutrients consist of nitrogen, potassium, and phosphorus—the NPK ratios you commonly see on fertilizer labels. These three nutrients serve as the backbone for the plant. Secondary nutrients include calcium, magnesium, and sulfur. They are called secondary nutrients because plants require them in smaller quantities in comparison to the primary nutrients we just mentioned. However, secondary nutrients are still required in larger quantities by plants in comparison to those classified as micronutrients such as boron and molybdenum. Today’s Get Amped Up blog will be focusing on the importance of calcium and the roles it plays in plants and in soil structure. Amp Agronomy’s product line offers several calcium-based formulations—two of the most popular being MegaCal™️ and SurCal+™️. Learn the difference between these two products and why each is essential to your crops, sod, or turfgrass for a variety of reasons.

The Role of Calcium in Plants

Calcium is ultimately essential to plant nutrition. It includes many roles that include:

  • Participating in metabolic processes of other nutrient uptakes,
  • Promoting proper plant cell elongation,
  • Strengthening cell wall structure as it forms calcium pectate compounds that give the cell walls stability and binds cells together,
  • Participating in enzymatic and hormonal processes,
  • Helping plants resist heat stress,
  • Helping plants resist disease,
  • Increasing overall fruit quality,
  • Regulating the stomata, and
  • Promoting a flocculating soil structure.


When this relationship is in balance, successfully maintaining plants becomes much easier as Mother Nature begins doing most of the work for us.

Factors Affecting the Availability of Calcium to Plants

When in the soil, calcium forms insoluble compounds with other elements, such as the primary nutrient phosphorus, that plants can not absorb. These compounds are not available to plants, so calcium is often tied up in the soil before even reaching the plant’s roots. For example, calcium carries a positive charge, so it tends to get absorbed into the surface of clay soil that contains a lot of negatively charged organic particles. If you look at the image below, you will see a representation of calcium and phosphorus getting tied up in soil.

Fun Fact: Positively charged ions, such as calcium, that are absorbed to soil particles are termed “exchangeable ions” because they can be exchanged by other ions present in the soil solution. Soil analyses determine the level of exchangeable calcium ions—not the total calcium in soil— because the exchangeable calcium is the form which is available to the plant.

There are several soil characteristics that increase the likelihood of calcium in the soil becoming available to the plant:

  • Higher Soil pH – soils with a higher pH level contain more available calcium,
  • Higher Soil CEC – describes the total amount of positively charged exchangeable ions that the soil can hold. A higher CEC indicates a higher capacity of calcium held and absorbed into soil (higher calcium availability),
  • Lack of competing ions – positively charged ions such as sodium, potassium, and magnesium that decrease calcium uptake.

Mobility and Uptake of Calcium by Plants

Once calcium has been made plant available and ready for absorption, the plant then consumes the nutrients and calcium mobility comes into play. The plant’s action of uptaking calcium is passive—it does not require energy from the plant. Calcium mobility takes place mainly in the xylem in combination with water. Therefore, it is directly related to the plant transpiration rate. See the image below to see a diagram of the xylem in plant roots.

Other Reactions of Calcium in Soil

One of calcium’s many benefits includes its ability to stabilize soil structure. The calcium that is absorbed into soil particles helps in the stabilization of the soil structure. Frequently, sodium is often absorbed, which causes the soil to crack, dry, and swell up when wet. Calcium works in opposition to sodium as it stabilizes soil structure so that water and other nutrients can reach plant roots.

Calcium Deficiency

Calcium deficiency is usually a result of low calcium availability or water stress, which results in low transpiration rates. The symptoms of calcium deficiency include curling of young leaves or shoots scorching or spotting on young leaves, poor growth, leaf tip burns, stunted root growth, and damage to fruit. It shows up first in new growth & the ability of plants to stand upright. Root mass is restricted, blossom end rot in fruit occurs, and there is sometimes manganese toxicity in soil due to low pH. As previously mentioned, the best way to diagnose a calcium deficiency is to conduct a soil analysis that determines the level of exchangeable calcium ions because exchangeable calcium is the only plant-available form of calcium. Taking a pH reading of your soil is also sometimes helpful as soils with a lower pH level contain a decreased amount of available calcium.

The above images illustrate blackheart in celery and blossom end rot in an artichoke and tomato. Blossom end rot is a physiological disorder caused by a calcium deficiency imbalance within the plant also occurring in pepper, squash, cucumber, and melon fruits. Photo credit to: Cornell University, University of California, and Arbico Organics.

MegaCal vs. SurCal+

Amp Agronomy’s product line offers several calcium-based formulations—two of the most popular being MegaCal and SurCal+. Although both products are calcium-based liquid fertilizers, there is a stark difference between these two, and each one is essential to your crops, sod, or turfgrass for a variety of reasons. In summary, MegaCal helps calcium get into your plant for the plant’s overall health, whereas SurCal+ ensures soil stabilization by creating a healthy soil structure for other nutrients to properly pass through upon application. In other words, MegaCal’s benefits include those that assist the plant’s overall growth and health. SurCal+ is designed specifically for the soil. MegaCal is 20 percent calcium, providing a large dosage of calcium in combination with other micronutrients and SurCal+ is 10 percent calcium.



A common tradition amongst farmers, turfgrass managers, and golf course superintendents is to apply gypsum, lime, or calcium nitrate to soils when plants are in need of calcium, or when soil pH is too low. While these three solutions are relatively inexpensive, none of them provide calcium that is readily plant available—with a vast majority of the application lost in soil tie-up due to phosphorus and other negatively charged ions. With the use of Catalyst Technology that encapsulates and protects individual nutrients from soil tie-up, MegaCal contains more than 70 essential nutrients that are readily plant-available. MegaCal provides calcium to help build stronger plants and promote healthier growth with the industry’s most cost-effective solutions for efficient calcium nutrition.


A wide variety of soil construction problems include soils that are either “dispersed”, allowing too much water into the soil and essentially drowning the roots, or soils that are “compacted,” keeping water out of the micropores where nutrients are taken up. Soil moisture issues and salinity management issues are common symptoms of calcium deficiency in soils. Calcium is proven to be an essential ingredient to building flocculated, or properly structured soils, for maintaining critical micropore spaces for root development and nutrient uptake. SurCal+ adds an important surfactant to carry calcium where it is most needed while lowering soil surface tension for better water movement.