The plants that we we grow need some essential nutrients. Primary, they get these from the soil to grow and give us wonderful flowers and delicious fruits. Many times, however, the soil does not contain enough nutrients to meet their needs. This situation we need to apply fertilizer, to keep them healthy and strong.
Fertilization is one of the most important cultivation tasks, along with watering, pruning and plant protection. Talking about fertilizer for plants, we are referring to natural or chemical substances. These contributes to the rooting, growth, flowering and fruiting of plants. Using fertilizer on our plants, we enrich the soil with nutrients. Also. it will replenish the elements that are absorbed during the cultivation of plants.
Especially when we have potted plants on our balcony or in our yard, the need of fertilization at regular intervals is even more imperative. So let’s see in detail what are the basic types of fertilizer, when we need to put fertilizer on plants and how to choose the right fertilizer.
There are a variety of fertilizer that we can find in the market. These vary depending on their origin and form. Depending on their origin, fertilizers are divided into:
Organic fertilizers come from the decomposition of plant and animal residues. They are approved for use in organic farming, which is why they are often referred to as, organic fertilizers. They can be characterized as manure, compost, seaweed fertilizer, and others that are commercially available.
Organic fertilizers have the advantage that they are environmentally friendly. They also contain organic matter that improves the natural properties of the soil. In addition to providing plants with nutrients, they also improve the ability of the soil to retain water and nutrients.
This type of fertilizers result from the synthesis of chemical elements through various chemical reactions and are the largest category of fertilizers used by growers. Chemical fertilizers have the advantage that they are lower in cost.
They also offer many possibilities to growers, due to their varied composition, at all stages of cultivation. Examples vary from rhizome and plant growth to fruit set and fruit production.
Organochemical fertilizers are a combination of chemical and organic fertilizers. They contain both chemical elements and an amount of organic matter. In other words, organic fertilizers are relatively cheaper than organic fertilizers, have a varied composition and are suitable for many crops, while improving soil characteristics.
In how we choose the right fertilizer, we say depending on the form. You should know that there are granular and crystalline fertilizers that are in solid form. But also you can find fertilizers in liquid form:
These are fertilizers in the form of granules. Granular fertilizers are usually absorbed more gradually by the soil and the root system of plants. In granular fertilizers, each grain contains proportionally all the nutrients of the fertilizer. There are also mixed or blend fertilizers, which have a granular form but in which the raw materials are simply mixed.
These are fertilizers in powder form. Crystal fertilizers are supplied in solid form and are water soluble, ie they dissolve very easily in water and are absorbed directly by plants through watering.
Liquid fertilizers are dissolved in water and applied through the irrigation system during watering or by spraying the foliage of the plants. In fact, they are very common in amateur formulations, as because they are water soluble we can very easily apply them with a watering can. Liquid fertilizers have the advantage of immediate absorption especially through sprays, when there are problematic soils.
In each fertilizer, either chemical or organic, on the label on the package, three basic numbers are indicated. These indicate the percentage (%) content in the three basic nutrients, in order: nitrogen, phosphorus and potassium.
Nitrogen as a fertilizer for plants promotes rich vegetation, rapid growth, higher height, larger leaf area and intense greenery on the leaves. The addition of phosphorus to plants contributes positively to a number of important functions, such as rapid growth of a strong root system, formation and good growth of flowers and creation of quality fruits and seeds.
The addition of potassium to the plants helps to create quality fruits of the crops, both in size, color and taste, while offering greater resistance of plants to adverse conditions of frost, strong winds, drought.Fertilizers may contain other nutrients that are lower in content such as magnesium, calcium, iron, zinc and boron.
Magnesium and iron help to green the leaves and ensure rich vegetation. Calcium significantly enhances the consistency of the fruit so that it does not soften easily, increases the size of the fruit and improves their quality. Finally, boron and zinc are very important for the flowering and fruiting stage and contribute significantly to improving overall production each year.
The choice of the appropriate fertilizer depends on many factors such as the type of crop, the soil in which we grow, the growth stage of the plant, the composition and form of the fertilizer, what function of the plant we want to contribute, as well as the economic its cost.
Especially for professional crops, before proceeding with the selection of fertilizer, it is important to do a soil analysis so that we can accurately determine the type of fertilization and the amount of fertilizer that our field needs. Below we list some key features that will help us in choosing the right fertilizer.
If we want to help the growth of plants, we use a fertilizer with a high content of nitrogen (N). To enhance the rooting, but also the flowering of the plants, we use fertilizers with high content of phosphorus.
If we want to improve the production and fruiting of the crop, both in quality and quantity, we choose fertilizer with high content of potassium.
As initial (basic) fertilization in horticultural crops and fruit trees, we usually use granular fertilizers. This is because they are slower to release, meaning they release nutrients over a longer period of time.
They usually contain all three basic nutrients, nitrogen, phosphorus and potassium. In these cases, the fertilizer can be spread throughout the field or placed only at planting sites to reduce costs.
When we want to reduce the cost of fertilizer in relation to the content of nutrients, we usually choose chemical fertilizers. We usually find them in granular form, that are generally cheaper.
Growing plants in degraded soils, it is necessary to use ecological granular fertilizers. This is the way to improve soil characteristics and their nutrients are more easily absorbed by plants. Also, in degraded soils, leaf spraying (foliar spraying) with nutrients with liquid or water-soluble fertilizers is offered.
In case we want immediate absorption of the nutrients, like in the case of calcium to treat the dry top of the tomato or boron for the fruiting of the olive. You should have in mind to choose liquid or water-soluble crystalline fertilizer. The type of these can be applied foliarly by spraying.
For our vegetable garden, we choose ecological fertilizers. These ones are environmentally friendly and help in the production of good quality fruits.
For ornamental plants that we have in pots, we choose chemical crystalline or liquid fertilizer. This type dissolves in water and it has good absorption by the plants, without the risk of excessive fertilization.
Fertilizer provides nutrients that help plants grow. However, there are some cases where we avoid putting fertilizer on plants. One of them is immediately after transplanting, as the plant needs time to adapt.
In addition, we avoid applying fertilizer to plants that are not irrigated. Also,in conditions where the plants are vulnerable. Examples are in periods of very high temperatures or the ones of very low temperatures and frost.