Let’s Get Down to Fertilizer Basics



If you want your garden plants to be healthy, good-looking, and productive, it is crucial that you supply them with appropriate fertilizers. Sadly, more than 50 percent of American gardeners don’t use fertilizer.

In this blog post, we are going to take a quick look at important basics of fertilizers — the what, the why, the how, and more.

What’s Fertilizer?

Fertilizer is a substance applied to the soil to boost its fertility. Fertilizer can be organic (manure, compost, etc.) or inorganic (mostly commercial fertilizers). Either way, fertilizer supplies both macronutrients and micronutrients that lack in the soil.

Why Do I Need to Apply Fertilizer?

Virgin or fertile soil often provide all nutrients that the plant need. However, as you continue to plant, the land loses some of its fertility. With that said, garden plants are fertilized to supplement the soil’s fertility. In principle, plants need six major nutrients (macronutrients) to thrive. Plants extract naturally the first three from water and air — oxygen, carbon, and hydrogen.

The remaining three — nitrogen, potassium, and phosphorus — are supposed to be supplied by the soil, but if they are lacking, you will have to apply appropriate fertilizer. Plants need the proper amount of nitrogen to make proteins required to produce herbage. Potassium, on the other hand, is necessary for vigor; it helps regulate metabolism, build a tolerance to disease, and plays a role in making carbohydrates. Phosphorus is needed for healthy root growth, budding, flowering, and energy production.

Plants also need specific nutrients in small quantities. Known as micronutrients, these include calcium, magnesium, sulfur, zinc, boron, iron, chlorine, molybdenum, and copper, just name a few.

Synthetic vs. Organic: Which is the Best?

Organic and synthetic fertilizers supply nutrients in different ways. While synthetic fertilizer provides an immediate boost to plants, they don’t offer much towards improving soil texture and overall fertility. That’s because they are readily water-soluble.

Organic fertilizers are made from composted manure and other plant materials. They usually break down slowly and offer more micronutrients than synthetic fertilizer. As such, organic fertilizer should be applied into the soil in fall so they can release nutrients right on time for vigorous growth in spring.

Soil Application vs. Foliar Feeding

It so happens that plants take up nutrients 8-20 times more proficiently through the leaves than through their roots. That’s why it is important to apply foliar feed during critical stages such as flowering, budding, or transplanting time.

Getting to Know your Soil pH

Turns out, plants cannot absorb nutrients from the soil when the pH is either too low or too high. Conducting a pH soil test is essential to determine whether to use sulfur-based fertilizer (to lower pH) or lime to increase soil pH.


Fertilizer plays a vital role in supplying nutrients deficient in your garden soil. The choice of fertilizer depends on what your plants need most — nitrogen, phosphorus or potassium?