Lesser-Known Facts About Hydroponics
Throughout history, scientists and agronomists have been on a quest to discover effective methods of cultivation. They've conducted experiments with different plant varieties, aiming to encourage higher yields and faster maturation.
During such experiments conducted in soil, they faced challenges related to root diseases, oxygen shortage in the root zone, and ineffective watering practices, as a substantial amount of water would simply percolate deeper into the ground.
Let's delve into a bit of history: The earliest mention of hydroponic cultivation dates back to the 16th century. During this time, the Dutch chemist-physiologist Jan van Helmont conducted an experiment in which he grew a plant in a barrel, using only rainwater for irrigation. While the primary purpose of his experiment was different, it marked one of the earliest recorded instances showcasing that plants can thrive without traditional soil. Fast forward a century, and various scientists gradually uncovered the phenomenon of photosynthesis. It wasn't until the 18th century that researchers determined the three essential components for plant growth: water, carbon dioxide, and light.
MISCONCEPTION №1: Vegetables cultivated in greenhouses look artificial and seem "plastic"
Have you ever experienced a situation where you bought tomatoes that appeared slightly pink on the store shelves, only to find out when you sliced them for a salad that they lacked flavor? If you have, it's understandable why you might come to the conclusion that vegetables grown during the winter are of uncertain origin and quality, and may not be as nutritious as desired.
In reality, the usual scenario plays out like this:
In countries such as Turkey or Morocco, there are farmers who intentionally grow tomatoes for export. They carefully choose tomato varieties that are well-suited for transport, and these varieties typically tend to be less sweet and firmer than the regular ones.
To ensure tomatoes remain fresh during transportation (for a week or even two) and maintain shelf life for several days, they are typically picked when they are still green. Their color ripens during transit. Therefore, the tomato you selected may not have fully ripened in the greenhouse and may not have accumulated sufficient sugar content.
Contrast this tomato with those cultivated in your local area. Certainly, the greenhouse-grown tomato might come at a higher price due to the expenses linked to heating and lighting. Nonetheless, it delivers a more robust flavor, rendering it both a nutritious and delectable choice.
As time passed, wood chips emerged as a viable alternative to soil. From the 1950s onwards, the hydroponic approach to cultivating plants in containers filled with wood chips gained momentum. Thanks to its efficiency, it became a prevalent method in industrial plant production.
Carrying on with their experiments, scientists and agronomists determined that the application of water-soluble fertilizers provides the most favorable outcomes. Consequently, since the 1970s and up to the present day, agronomists have been watering plants in conjunction with fertilizers.
MISCONCEPTION №2: Vegetables cultivated in greenhouses are saturated with pesticides
The integrity of individual growers in controlling the use of pesticides plays a crucial role in ensuring the safety of their products. While inspections by relevant authorities are important, it ultimately falls upon growers to responsibly manage their pesticide usage.
Therefore, if you want a verified and safe product, choose local and make sure you are familiar with and have checked the use of health-friendly growing systems by the producers.А лучше, выращивайте свое!
HYDROPONICS IS A COMPREHENSIVE CONCEPT THAT INVOLVES CULTIVATING PLANTS WITHOUT TRADITIONAL SOIL, UTILIZING AN ARTIFICIAL NUTRIENT SOLUTION INSTEAD
Hydroponics makes the saying "You get out what you put in" truly and directly applicable.
Let's dive into it. When we cultivate plants in soil, we often lack complete control over their nutrient intake and growth processes.
When we use hydroponic method, we assume complete responsibility for the climate, water quality, and its composition, essentially "crafting" the nutrition for the plants ourselves. Consequently, the more effectively and precisely we tend to the plants, the higher the quality of their growth, and the greater the yield they generate.
The use of hydroponic cultivation increases yields by 30% to 100%, depending on the cultivated crops and the type of equipment used.
In contemporary discussions of hydroponic cultivation, we are generally referring to the practice of growing plants in a substrate. There are various substrate options available, such as sand, expanded clay, wood chips, peat, perlite, coconut coir, rockwool, and more. Cultivating plants in a substrate is considered an efficient and user-friendly approach. It enables you to meticulously track the nutrients supplied to individual plants and exercise full control over the cultivation process.
Moreover, the substrate is placed on special trays and supports, which makes it convenient for maintenance.
The most common substrates in greenhouses are peat for greens and lettuce, and coconut substrate and rockwool for flowers and vegetables.
The prevalent substrate in modern greenhouses is mineral wool, often referred to as "rockwool" due to its production from basalt, a volcanic rock.
The manufacturing process involves heating basalt to a temperature of 1600°C, causing it to melt and naturally form long fibers in a large centrifuge. These fibers are then compressed into cubes and blocks, creating the mineral wool substrate. This yields a completely natural and inert substrate without any impurities. The substrate's structure is notably porous, with pores constituting 97% of its composition.
The majority of European farms choose rockwool as it offers the best solution for high-tech greenhouses, which are predominant in European agriculture due to their advanced capabilities and efficiency.
Thanks to its pure composition and absence of impurities or other elements in its structure, rockwool enables the extremely efficient utilization of irrigation water, providing plants with exactly what has been introduced into the system.
As a part of the hydroponic cultivation process, the collection and recycling of drainage water play a vital role. The drainage water treatment system enables the conservation of 30-60% of the total water volume. Since the water in rockwool slabs is free from impurities and exits the drainage system in a clean state, it often undergoes low-pressure UV disinfection for treatment. This disinfection method helps retain nutrients during purification, leading to farms saving 10-20% on all fertilizers.
An important point to note regarding the use of rockwool in different countries is the challenge of disposing of used slabs.
Since rockwool substrate is essentially a stone material, it doesn't naturally break down. Europeans have found an excellent solution to this problem by establishing factories that purchase used substrate to manufacture bricks. Specialized companies collect the spent slabs and transport them for further processing. Unfortunately, in most countries, there are currently no such factories, leaving us with an unresolved issue regarding disposal.
The global trend of favoring locally sourced products, known as "local farming," is on the rise. Consumers are increasingly opting for berries, vegetables, and fruits cultivated by nearby producers. In response to this shift, more countries are prioritizing the development of their greenhouse industry and decreasing their dependence on imports. Many nations acknowledge that they can ensure product quality when it is grown within their borders and regulated by their standards.
As a result, a worldwide trend in greenhouse farming is emerging. The United States is expanding various types of small and large farms, Russia is building industrial greenhouse complexes, Mexico is forming farming clusters, and so on.
In all these countries, the question of disposing of rockwool is also becoming a significant concern, leading to the increasing adoption of coconut substrate.
Cocopeat substrate is commonly known as an organic substitute for rockwool. Essentially, it is a byproduct obtained during the extraction of coconut fiber from coconut husks. Until recently, it was primarily used in warm regions of Africa and Asia for greenhouse cultivation without advanced technology. In such projects, extensive control measures were not required, making the lower cost of coconut mats an important consideration for greenhouse growers.
However, the key benefit of this substrate lies in its straightforward disposal. Due to its natural composition and easy biodegradability, it can be effortlessly disposed of alongside plant debris.
Another benefit of cocopeat substrate is its cost-effective transportation. Cocopeat substrate is shipped in its dry form, taking up significantly less space in containers compared to mineral wool. Later, when the mats are placed in the greenhouse, they absorb water and become eight times heavier.
Disinfecting the drainage is also an option when utilizing cocopeat substrate, but it doesn't retain fertilizers since it involves thorough purification methods such as high-pressure UV or thermal disinfection.
In the «greenhouse equipment» you will find more comprehensive discussion of the equipment employed in hydroponic cultivation.