Fertilizer is a substance (as manure or a chemical mixture) used to make soil more fertile, i.e. any material of natural or synthetic origin that is applied to soils or to plant tissues (usually leaves) to supply one or more plant nutrients essential to the growth of plants.
Simply put, fertilizers are plant food.
The most important of these essentials are: nitrogen, phosphorus and potassium. They are called macronutrients because plants need high quantities of them in order to function properly. They are usually given an abbreviation NPK. This stands for nitrogen (N), phosphorus (P) and potassium (kalium in other languages, hence the chemical symbol K).
Because plants need a lot of NPK, they are often what’s missing, and has to be added to the soil.
That is why most fertilizers on the market that are commonly used in agriculture contain those three basic plant nutrients: nitrogen, phosphorus, and potassium.
Secondary and micronutrients
But, besides macronutrients, for a balanced diet the plants also need secondary nutrients: sulfur, calcium, and magnesium; and micronutrients: boron, cobalt, copper, iron, manganese, molybdenum and zinc. Now, remember again that fertilizers are plant food and for better understanding compare them to human food: NPK for plants is like carbohydrates, protein and fats for people. Same as plants with NPK, we need a good balance of CPF.
But, would you feed your child with food that consists only of perfectly balanced carbohydrates, protein and fats? With no minerals, vitamins, trace elements? No, you most certainly wouldn’t.
Fertilizer manufacturers are aware of that, and they’ve added trace elements and all other required nutrients in order to produce a well rounded product that wouldn’t require you to purchase any additional supplements.
But, again! Compared to your child’s diet it would be the same as if you feed him with carbohydrates, protein and fats with vitamins and minerals added in tablets.
Any why not bring up your kids on a wholesome diet with plenty of organically grown fruit and vegetables?
Bear in mind the most important thing: natural and organic fertilizer differs from chemicals in that they feed your plants while building the soil and not taking anything from it, while soil fed with chemicals gradually deteriorates, becomes lifeless and unable to hold water and nutrients. Plants are poorly fed and need an increased amount of nutrients, grow weak and scarce.
Soils with lots of organic material remain loose and airy, hold more moisture and nutrients, foster growth of soil organisms, and promote healthier plant root development.
Think of organic fertilizers for your plants as of a balanced, well-rounded diet for people.
There are natural, organic fertilizers that aren’t made by mixing chemicals together. Organic fertilizers are made by mixing natural ingredients, ingredients that are naturally high in N or P or K or all of them, and that also contain trace elements.
People who eat a balanced, wholesome organic diet do not need supplements, added vitamins or anything else, and the same is with plants grown on healthy soil with lots of organic matter, teeming with worms and beneficial microorganisms. Like people, plants also have an immune system: if they are fed properly, they grow strong and can successfully fight plant diseases and pests.
Unfortunately, few of us are lucky enough to start with perfect soil. What we need to learn is how to get wholesome fertilizer for your garden.
Best organic fertilizers
Luckily, the best organic fertilizers are free!
Compost and grass clippings
They enrich the garden soil with nutrients that plants and microscopic soil life-forms are eager to use. You can easily collect grass clippings from your neighborhood or your own yard waste compost.
As most organic fertilizers are bulkier than synthetic chemical products, so their N-P-K percentages are typically lower than synthetic products, and their application rates are higher. Also, because organic products are biologically active, their NPK numbers change from bunch to bunch, which makes it impossible for producers to label it correctly and according to laws.
As a result, some excellent organic fertilizers are often not labeled as a „fertilizer“.
But make no mistake, compost and grass clippings do what fertilizers are supposed to do, and better than any industrial product!
Finally, what is the point in having a home garden if it’s not going to be organic?