Growth Minerals: Impacts on Yield and Quality

February 6, 2023

We all desire plants that are strong and robust, resistant to pests and diseases, and that end up with a healthy yield. But how do we actually achieve this? What are some steps that we can take that help bring us closer to what we really want?

Let’s dive in for a quick little overview:

There are four major growth minerals: nitrogen, potassium, chloride, and calcium. These four minerals have the greatest impact on growth. These growth minerals are important for all plants, both vegetative and reproductive, to build plant frame. Growth, the framing stage, always comes first, even for reproductive crops.

What we need to recognize is that not all growth energy is the same; the first three minerals: nitrogen (particularly the nitrate form), potassium, and chloride, tend to focus on shoot growth, rather than root growth, because they trigger a plant hormone called auxin. Calcium, on the other hand, triggers a hormone called cytokinin, which focuses more energy on root development but then also gives good growth as a result. It promotes a stocky plant with short internode spacing and large roots, which is exactly what we want.

This is not to say that nitrogen, potassium, and chloride are not important, because they are, we just can’t have the majority of our growth energy coming from them because they tend to focus on shoot growth rather than root growth.

Let’s use onions as an example of what we are talking about: Onions need a lot of nitrogen to bulb properly so that we get a large size. The challenge is when the nitrogen comes in the form of nitrate: we can get a large size onion, but it will NOT store well, but will rot shortly after storage begins. But if we use an amino acid or protein form of nitrogen, with adequate amounts of calcium, we can get a large onion AND have it store well.

I’ve alluded several times to the fact that there are differences in which form of nitrogen you use. This is an important discussion – we’ll focus on nitrates versus amino acids: Nitrates trigger rapid but weak growth, long internode spacing, and watery cells, so definitely the worse from a plant health perspective. These watery cells attract insects and diseases. Nitrates typically consume energy, triggering low brix.

Amino Acids, on the other hand, are stable forms of nitrogen that contribute much more to plant energy, help keep plant growth balanced, and have some other interesting responses, such as improved calcium uptake. We’ve also noticed that not all amino acids are the same from the perspective of calcium uptake. Several amino acids, such as those in Amino Blend, are in ratios that we see giving the best calcium uptake response.

Want a visual indicator in the field of how you’re doing with all this? Use a refractometer to get an idea where the brix are, then carefully note the internode spacing on your plants. The internode is where a branch branches out from the main stalk. Check the space between two branches: The shorter the internode spacing and the thicker the stalk, the healthier that plant is.

In summary, the way we feed plants has a substantial impact on their development. If we want to grow healthy and robust crops that will store well, we need the majority of our growth energy coming from calcium. Nitrogen is also needed for growth, but too much of it or not in the right form can create a quality issue. Also, specific amino acids both improve plant health and also improve calcium uptake substantially.