Fertilization part 1
A difficult topic for many growers, the difference between life or death for many plants. The following advices are general guidelines and plant behavior is always subject to local circumstances. Growers should always follow up on local legislation and consult a professional agronomist when in doubt. Syngenta does not accept any liability in any business damage resulting from the advice.
Food for plants
A plant exists for more than 90% of water. The rest is organic and inorganic substance, partly made by the plant itself and partly taken up from the environment. At school we all learn that plants make organic matter, through photosynthesis. Sugars, carbohydrates and proteins are created from H2O and CO2 in the green parts of plants. The assimilation process of making organic matter is influenced by temperature and light. Plant roots can take up all other required materials from the soil to build and feed the plant. That’s why there must be enough stock of all required inorganic materials in the substrate. It’s an important part of the growing process were the grower can (and must) influence the growth and development of his crop.
We divide the nutrient elements into two groups. Major elements are required in big quantities by plants. Minor elements are needed in small amounts. But these minor elements are strictly indispensable. You can compare this with petrol and oil in your car. The distance you can drive is depending on the availbale amount of petrol, but you always need oil. Even if you only start the engine. So, the minor elements are as important as the major elements.
|The major elements are:||Importance if you look to the ratio inside of plants:|
|The minor elements are:||Importance if you look to the ratio inside of plants:|
All these elements play a different role in the whole process, but you need all of them. The question for the grower is how much he must give, when, and how. This is comparable a mother feeding her baby. The amount and type of food depends on the age and the size of the baby. The first days, babies only drink milk. And when they grow bigger they need more food, like fruit, potatoes, vegetables, bread, milk, meat and so on. Realize that the breast milk contains all the elements that a baby needs during its first days, like Calcium, Iron, Proteins, Vitamins etc. Knowing this, there are two questions to answer. First: what is the ratio between the elements? Second: which amount should I give for a good growth? When we translated these questions to plants, a few other questions come up, namely:
- What is the optimum quantity per element that you are looking for?
- What is already available in the soil?
- Which elements do you have available in the water you use?
In general, the bigger the plant, the more fertilizer it needs (in absolute quantities). The fresh substrate in which the young plants are transplanted contains a reasonable amount of fertilizer for making new roots. From the moment of transplanting and watering, the amount of available fertilizer is decreasing. Therefore, you should always put fertilizer in the water to keep the nutrition level at least the same as it was before planting. The first time after transplanting you could apply plain water to make the roots connect better with the substrate. From that moment on, apply fertilizer with around 0.8 to 1.0 EC. Liquid fertilizer is preferred, to maintain the stock of food in the soil. But also, to avoid big changes in EC level in the pot. Plants do not like mayor changes in nutrition.
Depending on the development of the crop, the EC should be increased every week with small steps. Start with around 1.0 EC and increase with 0.2 - 0.5 EC, step by step. For instance, 1.0, 1.2, 1.6, 2.0, 2.5. Inspect your crop regularly. Pay attention to the color of the youngest leaves. Also, the color of the oldest leaves can give an indication if the fertilization is correct. Last but not least, the development and the color of the roots indicate clearly whether the plant is satisfied. The best way is to administrate your fertilization scheme, inspect your crop development, and make a soil analysis several times to check the balance and stock of fertilizer. Soil analysis can improve especially crops like Cyclamen, Primula acaulis, Pansy or Gerbera, because these have a long crop time.
With this experience, based on your specific climate and the water quality, real growth improvements can be achieved. A good and helpful tool for a grower is an EC meter. When used right, this meter gives you a clear indication about the EC changes in the pot. This is helpful to decide the next drip EC level.
- Ready for use mixtures (NPK)
- Single element fertilizers
- Leaf fertilizers
- Slow release fertilizers
Ready for use mixtures
- Very good soluble
- Available in many different ratio’s
- Easy to use
- Relative high price per kg
- Too low amount of minor elements
Single element fertilizers
Slow release fertilizers
Working of slow release fertilizer
|Water goes in via osmosis||Water goes out again with fertilizer|
- This is the choice for a mix from shorter and longer activity time, for instance 50% 12-14 months and 50% 16-18 months.
- Second option to change completely to a longer-term variety.
- Third option is to avoid over-feeding by lowering the amount per m3.
Relation release speed with temperature
|Wrong fertilized||Good fertilized|