Howdy family, Jeffrey here from “grown zero” in Berea, and I’m mostly just happy because I haven’t made an awful blog pun in a while. (Is awful really the word, though?) This week’s informative post is all about nutrients, so… off we go!

Plants feed people, and nutrients feed plants. (As for what feeds nutrients, philosophers have speculated for some time and will surely continue to do so.) Some of these nutrients, like carbon (C), hydrogen (H), and oxygen (O), are mostly beyond your control. Your plants get these non-mineral nutrients from water and sunlight and transform them into the starches and sugars that they require.

Plants get their other nutrients—the ones that you have more control over—from the soil, absorbing nutrients that have dissolved in water through their roots. The ability for plants to absorb nutrients is determined by a number of factors, including the texture of your soil, as well as its pH—which is a measure of soil acidity. While the topic of pH is complex, the basic idea is that different nutrients are more or less accessible by plants depending on how alkaline or acidic the soil is. (Don’t fret! A blog about pH is coming next week.)


The three most important nutrients, called macronutrients, are nitrogen (N), phosphorous (P), and potassium (K). (As a general rule, macronutrients are harder for plants to access in a soil that has a low pH.)

As one element of photosynthesis, nitrogen is a very important nutrient for plants, and it makes part of all of a plant’s living cells. On a practical level, nitrogen helps with the growth of leafy plants, causing rapid plant growth. Since nitrogen is so important in the creation of chlorophyll, just remember that if it’s green, it needs nitrogen. (That’s not a very catchy slogan, but it’s true.)

Phosphorous, too, plays a role in the photosynthetic process. Much of the benefits of phosphorous center around root development and blooming, and without it, your plants would not be very hardy.

Potassium is a vital nutrient for fruit-bearing plants, ensuring that the fruits of your labor are as juicy as can be. Potassium can be supplied to your plants by soil minerals, organic materials, and fertilizer, but more on that later. 🙂

Three other somewhat-secondary macronutrients include calcium (Ca), which makes up part of a plants cell walls, magnesium (Mg), another key player in generating chlorophyll, and sulfur (S), which benefits your plants in numerous ways, including in the production of proteins.

Finally, all of these biological processes of plant are supplemented to a smaller degree by micronutrients (also called trace elements) like boron (B), Copper (Cu), Manganese (Mn), Molybdenum (Mo), Zinc (Zn), Iron (Fe). (Unlike macronutrients, theses micronutrients are less accessible for you plants when the soil has a high pH.)


Fertilizers are your means of delivering these different nutrients to your hungry plants. Some fertilizers are organic, while others are inorganic. The first category, which includes things like compost and manure, can be appealing from a more philosophical standpoint since they come from natural materials, while the second category is appealing due to the fact that it is soluble and can therefore be consumed by your plant quickly. (They do have the drawback of not improving the structure of your soil and potentially polluting water sources due to how quickly they release nutrients, but there are better and worse ways to use them.)


The composition of a particular fertilizer is given in the form of an NPK ratio, which tells you what percentage the fertilizer contains of those three most essential nutrients. This is particularly useful, because soil recommendations are often framed in terms of this ratio. Essentially, if a fertilizer’s packaging has the ratio (12:10:5) on it that means that 12% of the fertilizer is nitrogen, 10% is phosphorous, and 5% is potassium. These numbers don’t add up to 100% because the package will also contain trace elements as well as filler.


I wanted to close this blog with a few assorted recommendations for folks who are curious about what to use to improve the nutrient availability in their garden.

Nitrogen: Manure, poultry waste, blood meal. (These are organic options have the benefit of building up the organic matter of your soil.) Ammonium sulfate and ammonium nitrate are some inorganic options. Crop rotation can also help; plant legumes in an area and allow the bacteria in their roots to restore your nitrogen.

Phosphorous: Bonemeal and manure are some organic options. Superphosphate is a more fast-acting choice.

Potassium: Compost, wood ash, kelp—these are all great organic choices for you. Potassium chloride is a very, very rapid inorganic option.

Until next time,

Jeffrey Helton
AmeriCorps VISTA