April 19th, 2022 - Know your Nutrients - post by our Avid Gardner Ravi Rokkam

I know many of you are gardeners and would like to know what makes up fertile soil. You would also understand that adding fertilizers would improve it. Have you ever been in the fertilizer aisle of a garden or farm store? You are faced with a dizzying array of fertilizer options, many with three numbers like 10-10-10, 20-20-20, 10-8-10, or many other combinations of numbers. You may be asking yourself, “What do the numbers on fertilizer mean?”. These are NPK values, which leads to the next question, “What is NPK?”. These are macro-nutrients - nitrogen (N), phosphorus (P), and potassium (K), or NPK for short.

So how do you read these numbers? For example, if you purchase a 10-pound bag of fertilizer labeled 5-10-5, it contains 5 percent nitrogen, 10 percent phosphorus, and 5 percent potassium by weight. The remaining 80 percent of the bag's weight is comprised of minor nutrients or fillers.

So now that you know what the numbers on fertilizer mean, you need to understand why NPK is essential to your plants. All plants need nitrogen, phosphorus, and potassium to grow. Without enough of these nutrients, a plant will fail to produce healthy.

Nitrogen (N) – Nitrogen is mainly responsible for the growth of leaves on the plant. Phosphorus (P) – Phosphorus is primarily responsible for root growth and flower and fruit development. Potassium (K) – Potassium is a nutrient that helps the overall functions of the plant perform correctly. Knowing the NPK values of fertilizer can help you select one that is appropriate for the type of plant you are growing. For example, if you are growing leafy vegetables, you may want to apply a fertilizer that has a higher nitrogen number to encourage lush growth. If you are growing flowers, you may want to use a fertilizer that has a higher phosphorus number to encourage more blooms.

Apart from the Macro Nutrients, the plants also need Micro Nutrients such as Calcium, Iron, Magnesium, Sulfur, etc., which are part of the soil/fertilizer.

Organic vs. Synthetic Fertilizers, what are they made of?
Organic fertilizers are called the black gold of the farmers and are made from natural ingredients. They often have lower concentrations of the three macronutrients, so you need to use more significant amounts. However, they contain many other nutrients that feed both the plant and the soil. Organic fertilizers are made from naturally occurring mineral deposits like phosphates and organic material, such as eggshells, coffee grounds, bone or plant meal, or composted manure. Below is a video detailing various other organic fertilizers, which I found very interesting.

Synthetic fertilizers are made by chemically processing raw materials, and they are water-soluble and can be taken up by the plant almost immediately. In fact, applying too much synthetic fertilizer can "burn" foliage and damage your plants. Synthetic fertilizers give plants a quick boost but do little to improve soil texture, stimulate soil life, or improve your soil's long-term fertility.

In general, the nutrients in organic fertilizers are not water-soluble and are released to the plants slowly over months or even years. For this reason, organic fertilizers are best applied in the fall, so the nutrients will be available in the spring. These organic fertilizers stimulate beneficial soil microorganisms and improve the structure of the soil. Soil microbes play an essential role in converting organic fertilizers into soluble nutrients that can be absorbed by your plants.

I would like to leave you with a couple of photos from my little garden.