What is Fertigation?
Fertigation, also called nutrigation, is a fertilizer application method in which water soluble fertilizers are dissolved or diluted into water and delivered to the crop through the irrigation system. The irrigation delivery system may be drip, trickle, flood, or sprinkler. Even center pivot irrigation systems can be used to Fertigate crops.
Using Fertigation, an adequate supply of nutrients and water can be directed towards the plant root zone to satisfy plant demands during the various growth stages.
- Nutrients are directed to the active root zone
- Uniform distribution of nutrients
- Nutrients are already dissolved, hence ready for uptake by the roots
- The plant enjoys a continuous supply of nutrients. No temporary deficiency may occur to slow growth
Fertigation allows precise and targeted application of water and fertilizers to the root zone. Unlike broadcast fertilizer application, drip irrigation allows for precise amounts of water and fertilizers to be applied in close proximity to the root zone of each plant.
Nutrients can be applied at the time they are most needed by the crop. In the absence of a fertigation system, it is difficult, or even impossible, to apply fertilizers when plants are larger and access to the crop is limited. In such cases, fertilizers are often applied too early, resulting in losses of nutrients due to leaching, run-off, volatilization etc.
In most types of fertigation, this limitation does not exist. Once the fertigation system is installed, fertilizers can be easily applied at the right growing stage, according to the requirements of the crop.
Applying precise rates of fertilizers.
Advanced fertigation systems can reach highly accurate application rates by using high-tech equipment, such as injectors and computerized control systems, which are carefully calibrated and adjusted. Automatic adjustment of injection ratios of the fertilizer solutions from the stock tanks to the irrigation water relies on input from EC and pH sensors, as well as water and fertilizer flow meters.
In addition, more than one stock tank can be used, giving the grower the flexibility to apply different nutrient profiles to different plant zones, or at different times, by adjusting a different injection ratio for each tank.
Nutrient availability and plant uptake efficiency are better.
Because fertilizers are dissolved in irrigation water, nutrients can be instantly absorbed by the plant, as soon as they are applied.
The key parameters of a fertigation program
Before designing a fertigation program, several factors need to be taken into consideration:
- Soil: the soil analysis is a very important factor in determining the fertilization plan; knowledge of the nutrient levels in the soil means the grower can adjust the fertilization plan (adding or reducing nutrients). The pH of the soil makes it possible to predict which nutrients will be available in large or small quantities for the plant roots.
- Water: the water analysis is important as it informs the grower which nutrients the water will supply. The common nutrients in water are: Ca, Mg, and Cl. Knowing the pH levels of the water allows a grower to choose the best formula for his/ her conditions. For example, if the pH levels of the water and the bicarbonates are high, the grower will choose fertilizers with an acidifying effect to neutralize the bicarbonates and to reduce the pH of the water. (More information is available in the ‘water quality’ section).
- Crop demand: knowing the nutrient demands of various crops during the growing cycle allows the grower to create an accurate fertilization plan that will result in an optimum yield.
- High quality, fully water soluble fertilizers are required for the preparation of appropriate nutrient solutions.
For a comprehensive review of Fertigation read this pdf:
Fertigation: A Tool for Efficient Fertilizer and Water Management.
First edition, IFA, Paris, France and IPI, Horgen, Switzerland, May 2011
Copyright 2011 IFA and IPI. All rights reserved
This document offers guidance for applying pesticides and fertilizers through an irrigation system when growing marijuana either indoors, outdoors, or in a greenhouse.
Technical Information Bulletin No. TIB 01.16 | Pesticide Management Division | Compliance Program | firstname.lastname@example.org
High yielding cannabis production systems almost always have drip irrigation delivery and automated fertilizer injection systems. When choosing a fertigation system design their are a few considerations that will determine which system best fulfills your needs. System specifications like water flow and water pressure affect the operation of fertilizer injectors and options like multiple zones, stock tanks and the ability to automatically change the fertilizer working solution formula will all play into the determination as to which system design you choose. Custom Hydro is available to help with fertigation system design. Contact us today to get started.
Please review these helpful documents from Grodan Stonewool regarding crop steering using irrigation frequency and duration.
Crop steering can be achieved in part through irrigation helping the plant grow leaves (vegetative
growth) or flowers /fruits (generative growth). The amount of irrigation solution applied and the
frequency influences the plants response and steers the growth. Adjusting the irrigation strategy
specifically for the environment, genetic, and stage of plant growth will keep the plant growth at the
optimum and improve final product quality.