11 septembre 2026

Fertilization Lexicon: learn agronomy with the Germis

By the Germis · Published on September 11, 2026 · Germiflor, Mazamet (Tarn, France)

CEC, NPK, pH, C/N ratio, clay-humus complex… In fertilization, good decisions often start with understanding the words.

Since 1885, at Germiflor, we have worked with soils, plants and the people who grow them. And we keep coming back to the same observation: behind many fertilization questions lies, first of all, a question of understanding. That is why we completely redesigned our Fertilization Lexicon (in French). Free and open to everyone with a simple sign-up, it brings together the essential concepts of agronomy (raw materials, the nitrogen cycle, pH, NPK, regulations) in illustrated fact sheets and clear definitions.

And in 2026, we are going further with the Germis Academy, the big new feature of this edition: 107 knowledge cards, 116 questions, four difficulty levels and a game-style progression to learn, test your knowledge and better understand what goes on beneath our feet. Your guides are our two mascots, Germi and Germinette. As the 2026 school year gets underway, let us show you around.

Illustration of the Fertilization Lexicon and the Germis Academy: Germi and Germinette surrounded by key soil concepts

Knowledge that makes soils sprout: the Lexicon and the Academy, free to access.

Why a fertilization lexicon? Vocabulary is the first barrier

Agronomy is complex. It shouldn’t be out of reach. If you don’t know what CEC is (cation exchange capacity: the soil’s ability to store and then release nutrients), you can’t understand why two neighboring fields respond differently to the same application. If you confuse fertilizer with soil amendment, you buy the wrong product for the right problem. And if you’ve never heard of Liebig’s law of the minimum (yield is limited by the most deficient element, not by the abundance of the others), you waste inputs where a single element was holding everything back.

Then there’s the confusion that stings us most, as a company that has made fertilizers and soil amendments since 1885: mixing up fertilizers and crop protection products (pesticides). Our trade is little known, so let’s put it simply. A fertilizer or a soil amendment feeds the soil and the plant. A crop protection product protects or treats a crop against a disease, a pest or a competing weed. Lumping the two together is like confusing the dinner plate with the medicine cabinet. This confusion skews public debate and makes buying decisions harder. We had already untangled it in fertilizers and pesticides: what’s the difference? The Lexicon was also created for that: to make our trade easy to understand.

Cause, action, effect: that is the whole logic of fertilization. But you still need the words to follow it. That is exactly the idea behind our introductory article, the Germis, your seeds of knowledge: explaining what happens in the soil, simply, without ever oversimplifying it.

Common mistake: asking for “a fertilizer” to fix a soil structure problem. A problem with structure, organic matter content or the soil’s biological activity is not solved simply by adding more nutrients. The soil amendment works first on the soil’s properties; the fertilizer then supplies the nutrients the crop needs, according to its requirements. Reversing the order is like watering the leaves of a tree whose roots are suffocating.

The learning method, in the same order as the field method

The same reflex as with soil: build the support (the concepts), feed it (practice), then adjust in the field.

The Fertilization Lexicon: a living dictionary of soil

A standard agricultural glossary is an alphabetical list. The Fertilization Lexicon is a learning path. Each concept gets its own illustrated fact sheet: a clear definition, a diagram when the eye grasps things faster than text, and the link to practice, meaning what it changes in the field or in the garden. You move through it by theme, not alphabetically, because soil can’t be read from A to Z.

Nine major themes structure the whole: the families of raw materials (mineral, plant, animal and specialty), the nitrogen cycle, the clay-humus complex (the “soil’s pantry” that holds water and nutrients), pH, the three primary nutrients NPK, trace elements, iron chlorosis, Liebig’s law of the minimum, and regulations with their labels. If you’ve ever wondered what soil is, exactly, you already know why these nine: they are the foundations of every fertilization decision.

What the Lexicon covers, at a glance

The nine themes of the Lexicon: each one opens onto detailed fact sheets illustrated with diagrams.

The Germis’ tip: start with the “clay-humus complex” fact sheet. It is the keystone: once you understand how soil stores and then releases water and nutrients, pH, CEC and the role of soil amendments suddenly fall into place. Ten minutes of reading that save you hours.

The Germis Academy: learning agronomy through play

Reading a definition is good. Recalling it from memory while standing in a field is better. That is the whole bet behind the Germis Academy, the big new feature of the 2026 edition: turning review into a game. In practice, the Academy offers 107 illustrated knowledge cards and 116 questions spread across four difficulty levels. You move at your own pace, earn experience, climb the ranks and unlock avatars as you progress. Cause, action, effect: you test yourself, spot what’s missing, go back to the fact sheet, and the concept sticks.

We wanted to bring together, in a single tool, two approaches that rarely go hand in hand: understanding through an illustrated lexicon, then checking your knowledge right away through games and quizzes. It is designed as much for the student preparing for a test as for the professional who wants to check a concept before making a decision. It is our way of extending the 6-step living soil method: giving you the keys to read the situation before handing you recipes.

Four levels to progress, from your first concept to field reflexes

The seed climbs: each level you complete reinforces the concepts of the one before, all the way to field reflexes.

The Germis’ tip: even if you work in the trade, start at level 1. Not out of modesty: out of method. The basic questions often reveal a concept you thought you had mastered, and that is precisely the one that costs you dearly when it’s time to plan an application.

141 years of know-how. And no reason to keep it to ourselves

Since 1885 in Mazamet, five generations have succeeded one another at Germiflor. Over 141 years, we have learned by formulating, observing soils, talking with farmers and sometimes questioning our own certainties. Until now, part of this knowledge was passed on by word of mouth, through our technicians and teams, or lived in the first version of our Lexicon. With the digital Lexicon and the Germis Academy, we decided to open it up to everyone. Because a good fertilizer never replaces an understanding of the soil. It works alongside it.

The Lexicon also explains what sets us apart: Mazor®, a 100% plant-based organic soil amendment produced through several months of composting, guaranteed to contain 1 billion microorganisms per gram, and its patented Cronops® manufacturing process. You will come across it in the fact sheets; to see how it is made, head to our manufacturing process. On labels, the Lexicon devotes an entire theme to regulations: approved for organic farming (AB), certified Vegan… these claims vary with the raw materials and formulas, and it is precisely by understanding the rules that you can read a label without getting it wrong.

Who is the tool for? Students, professionals, gardeners

Students and teachers: the 2026 school year is starting, and agronomy vocabulary comes up in the very first weeks of a BTS or bac pro (French agricultural diplomas) or a bachelor’s degree. The Lexicon works as a permanent study sheet, the Academy as a practice test: ten minutes of quizzes before class, and definitions stop being abstract. Teachers can use it in the classroom: the tool is free and works on computers as well as phones.

Farmers and technicians: between two growing seasons, a verified concept beats a habit carried over. Unsure about the antagonism between potassium and magnesium, the C/N ratio of a material, or what a pH of 8 really implies? The fact sheet is close at hand, the answer is short, and it is tied to practical work in the field.

Gardeners: you don’t need to be an agronomist to grow a successful vegetable garden. But understanding why you amend in the fall and fertilize in the spring changes everything, and your raised vegetable beds will pay you back. Level 1 of the Academy is made for you: it starts from the basics, without unnecessary jargon.

The tool in one table

Step	Where?	What you do there	What you gain
1. Explore	Fertilization Lexicon	Read the illustrated fact sheets, theme by theme	The right vocabulary, connected to the field
2. Practice	Germis Academy	Answer the quizzes, level by level	Concepts that stick, visible progress
3. Apply	In the field, in the garden	Observe, decide, adjust your inputs	Reasoned decisions, less waste

Checklist: getting started with the Lexicon and the Academy

☐ Create your free account on the Fertilization Lexicon

☐ Read your first three fact sheets: clay-humus complex, NPK, fertilizer vs. soil amendment

☐ Take your time with the diagrams: that’s often where the concept “clicks”

☐ Start a first level 1 quiz in the Germis Academy

☐ Note the questions you missed and reread the matching fact sheet

☐ Move on to the next level only once you’re comfortable with the previous one

☐ Keep up the pace: ten minutes a day for two weeks

☐ Students: align your sessions with the semester’s curriculum

☐ Professionals: check a concept before each fertilization decision

☐ Share the tool with those around you (colleagues, classmates, gardening club)

Frequently asked questions: Fertilization Lexicon and Germis Academy

▸ What is the Germiflor Fertilization Lexicon?

The Fertilization Lexicon is a free interactive glossary created by Germiflor, fully updated as a digital version in 2026. It brings together the key concepts of agronomy (raw materials, the nitrogen cycle, pH, NPK, regulations) in fact sheets illustrated with diagrams, connected to practice in the field and in the garden.

▸ What is the Germis Academy?

The Germis Academy is the Lexicon’s big new feature for 2026: a training platform with 107 illustrated knowledge cards and 116 quiz questions spread across four difficulty levels. You progress at your own pace, with ranks to climb and avatars to unlock.

▸ Are the Lexicon and the Academy free?

Yes, access is completely free. A simple sign-up (email address) is all it takes to open the full version: detailed fact sheets, animated diagrams and the Germis Academy quizzes.

▸ Who is the Germis Academy for?

The Germis Academy is for farmers, technicians, agronomy students and gardeners. The four levels let everyone come in through the right door, from beginner to seasoned professional.

▸ How can I review agronomy for an agricultural BTS or bac pro?

To review agronomy efficiently, alternate short reading with immediate testing: one Lexicon fact sheet, then the matching quiz in the Academy. Ten minutes a day is enough; the questions you miss tell you exactly what to reread before the exam.

▸ How is it different from a standard agricultural glossary?

A standard glossary lists definitions in alphabetical order. The Fertilization Lexicon organizes concepts by theme, illustrates them with diagrams and links them to a progression quiz: you don’t just read, you check that you’ve understood.

▸ Do I need a background in agronomy to get started?

No, none at all. Level 1 of the Academy starts from the basics (what living soil is, what the NPK numbers mean) and every Lexicon fact sheet defines its terms as it goes. The higher levels then take over.

Understand before you act

The Lexicon wasn’t designed to tell you which product to buy. It was designed to help you understand why, when and how to act.

Once you understand how the soil works and what the plant needs, it becomes much easier to tell a soil amendment from a fertilizer, read an NPK formula or plan an application. The same logic has guided our teams in developing more than 600 soil amendment and fertilizer formulas since 1885.

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