Kale is considered one of the most suitable crops for the hydroponic system. It is widely grown in different hydroponic farms across India because of its adaptability and nutrient richness.
Kale is known for its richness in flavor around the world. Its versatility and nutritional value make it a part of numerous international recipes.
Why it's better to grow kale in hydroponics? Kale's wide electrical conductivity range makes it easier to grow with other crops as well, and you can get a much diverse and profitable harvest.
The most commonly grown kale variety in hydroponics is Curly kale or Scots kale. Kale grows fast even in an indoor hydroponic farm, and that makes it a versatile crop.
Starting with the seeds
It is always a satisfying experience to see your seeds maturing into full-grown plants. Hydroponics have complete control over the elements, and that is why it is an excellent system for starting seeds.
Usually, seeds got placed in growing cubes for the germination process, but it will take so much time if you have bigger plans for your hydroponic farm. Many commercial growers use a Vacuum seeder to speed up the process, and you can also use pelleted seeds as they are wrapped in clay, making them easier to handle.
Kale seeds take around 5 to 8 days to germinate when provided proper care and management.
Type of Hydroponic Systems Used for Growing Kale
Kale plants have much larger roots, and that's why it needs more area for its growth. There are different hydroponic systems in which your kale plants can flourish comfortably.
1. Deep Water Culture (DWC) system:
A standard water culture system allows the roots to submerge in water. But to classify it as a deep-water culture system, the water should be at least 12 inches (30.48 cm) deep.
There are two types of DWC system in which kale can be grown:
· Floating Rafts: This type of system is usually adopted by commercial kale growers who are intending to grow more plants in their hydroponic system.
· Bucket DWC System: Mostly, hobbyists choose this type of system to grow kale in the comfort of their homes. The installation process of the Bucket system is very smooth.
2. Kratky Method:
The Kratky method is easy to control and manage, and it provides all the benefits of a hydroponic system without being time-consuming.
In the Kratky method, the plants sit in the net pots with the help of a suitable growing medium. The plant roots have partial exposure to air while the lower part submerged in the deep-water reservoir.
Both systems have their advantages and usability. The selection depends on the system's suitability for the grower.
Optimum Growing Environment for Kale
Temperature Required for Proper Growth of Kale: To grow healthy kale plants, you should maintain the temperature of your hydroponic farm between 16 °C to 24 °C.
Electrical Conductivity (EC) and pH range: Kale has a broader range of electrical conductivity, making it less susceptible to changes in the EC. EC range for optimum growth of the kale plant falls between 1.6 to 2.5.
The nutrient solution pH should be maintained between 5.5 to 6.5 for better growth of the plant.
Lighting Requirement: For indoor hydroponic farms kale crop is always considered a reliable choice because it can grow well under the artificial lighting condition. Far-red light can increase the yield of the kale plant. Sometimes a combination of green and far-red light is also used.
Management of Nutrients
Different nutrients have different roles in the development of the plant. Like all other leafy greens, kale also consumes high amounts of nitrogen during its vegetative growth phase. For the growth of bigger and healthier leaves, nitrogen is an essential element.
In the initial phase of development, when the roots are developing, the kale plant consumes more phosphorus.
Few things will help you manage your nutrient solution better, these are:
· Monitoring the EC of the nutrient solution: Frequent monitoring of EC will help you adjust the levels before things get wrong. High EC or low EC both affects the plant's nutrient uptake capacity.
· Measuring the temperature of the nutrient solution: It is an essential thing because high temperature drastically reduces the oxygen holding capacity of the solution. Plants absorb most of the oxygen from their roots, and it is necessary for root development.
The Kale crop will be ready for harvesting after 4 to 5 weeks from transplanting.
In hydroponics, there are always some areas where we can improve by experimenting with the system. The crop quality and yield both become more satisfying when a grower's skill unites with experience.