Role of Calcium and PH in Hydroponics

To understand the role of pH in hydroponics one has to backtrack to age-old soil growing. We know that soil has many macroelements and microelements essential for soil growing chief of which are nitrogen in the form of nitrates and phosphorus and potassium in their salt forms. Other microelements are calcium, magnesium, iron, molybdenum, zinc, copper, chlorine etc. The presence of these elements in their salt or chelate forms causes small acidic or basic compounds to form in the soil thus changing the overall pH of the soil. The effects of rain and other natural processes make changes to the pH of soil according to the changing seasons thus helping plants through their veg and flowering cycles. This has to be replicated in Hydroponics where we do not want natural processes to command our plant growth but rather induce pH and NPK ratio changes to achieve flowering or vegetative growth.

Hydroponics farming in India has to be careful about pH changes due to heat and water “hardness”. Water is considered “ hard” when there is a high amount of calcium present, This is a common problem in the water we get from bore wells and from corporation sources. The calcium in water can react with the hydroponic nutrients and make compounds out of the salt forms of the microelements that cannot undergo cation exchange with plant roots thus causing deficiencies and higher susceptibility to diseases. Therefore it is imperative that grower’s use RO or low EC water for hydroponic farming. The general guideline is a ppm below 30 or an EC below .3(mS/cm). Nutrients these days come with “soft” and “ hard” water versions which basically uses chemical forms to negate the effect of overactive calcium and preserve the ratios of mineral salts in the solution.

pH variation is achieved in hydroponics with the use of carefully formulated pH regulation solutions. These are usually made of phosphorus or nitrogen derived compounds such as phosphoric acid, nitric acid for acidic changes and sodium hydroxide in mild concentrations for basic changes. pH is recommended to be between 5.5 and 6.5 for hydroponics meaning a slightly acidic water medium. While some plants do like a more neutral or even slightly basic water medium, this is few and far between and 5.5-6.5 is the best bet to get great growth. pH dictates what nutrients are taken up. For example, better absorption of magnesium, molybdenum, and Sulphur happen at higher pH of about 6-7 but zinc, boron, and iron need lower pH of about 5-6, therefore, it may be useful to control pH during your growth stages based on the nutrients your plant needs more.

To sum up it is necessary to make sure the pH of your nutrient tank is measured and monitored whether doing hydroponics farming at home or on a commercial scale whether doing hydroponics farming in Bangalore<.a> or in Delhi and this can be done easily with the available equipment such as a pH pen as made by Bluelab or a pH test kit. The pen, of course, is the more accurate and simple option. For ph testing, it is imperative to have both the testing mechanisms and the regulation solutions. Make sure to use solutions from trusted vendors that do not mess with the NPK ratios or cause the growth of bad bacteria.

How to build Hydroponics system?

Building a hydroponics system can be as easy as placing a strainer over a bowl and sprinkling some fenugreek seeds on the top. Proof of concept apart when building a hydroponics system one must first decide on if they are looking to do this as commercial farming set up or to do hydroponic farming at home.

Someone with the plan of doing hydroponic farming in Bangalore would have to look at a commercial farm from the angle of where, how and what. The location, the technique of hydroponics and the what needs to go into this farm. For the purposes of this post, we will look into the what as it directly deals with the how to build aspect.

The first thing to do is to choose the crop, long rooted crops need larger vessels to hold this complex and fibrous root matter and shorter rooted plants can be manipulated to produce relatively lower plant material and maximize their usable growth. Hydroponic techniques consist of the following:

1.Nutrient Film Technique – Leafy greens and herbs

2.Deep water culture– Fruiting vegetables and vine crops

3.Ebb and flow tubs– Nursery growing and leafy greens.

4.Media beds– Microgreens and tender tubers.

Each of these methods is specialized or give the best growth with some crop varieties but does not work as a “one size fits all” method. This, in turn, brings out the beauty in hydroponics as it means that each growing method’s application can optimize resource use, material requirements, and cost.

To explain the principles of building a hydroponics system let us take a look at the NFT growing method.

An NFT system will require to grow channels or pipes with holes to place the plant holders, these pipes will have to be outfitted with inlet and outlet drainage to create a flow of water from one end of the growing channels to the other, the movement of water can be done with a pump. The grow pipes will have to have caps that dictate the level of water maintained in the pipe at the ends and plumbing to bring the water down into a central reservoir.

Having a central reservoir is a good idea as it reduces the need for parameter checks in multiple locations. The water parameters that are of utmost importance in hydroponics are pH and Electrical conductivity/ ppm/ TDS of the water.
The TDS dictates the number of dissolved nutrients and this varies with the age of plants. As with all living beings plants need more food as they grow and thus the TDS of a hydroponics system will increase over time.

pH is a factor that influences the individual uptake of growth necessary plant nutrients, pH levels for hydroponics are recommended to be between 5.5 and 6.5 as this is the optimal range in which all the 18 essential micro and macro elements plants require are taken up by the roots most readily.
Hydroponic systems also need to grow media the classical nature of these media is that they are inert and as such give no nutrition or boost to plant growth but rather touch upon other important aspects such as aeration, root support, and stem support. Commonly used inert media are washed coco peat, hydroton or Light expanded clay aggregate and rock wool. It is also important to note that some media are better for some types of systems and crops than other. For ex( media beds for microgreens usually have cocopeat whereas ebb and flow systems for nurseries of fruiting crops usually contain hydroton. Rockwool cubes are used commonly as seed starters.

Building a hydroponics system works best when reverse engineering from the needs of the plant, their life cycle and stages and to tie that into maximizing efficiency and output. Building a hydroponics system can be as simple or complex as you would like it to be.

Grow Your Own Plants In A Hydroponic System

The types of plants that can be grown on a hydroponic system, is controlled firstly by the Hydroponic System Design. There are three main types namely NFT( Nutrient Film Technique) DWC( Deep Water Culture) and media beds.

NFT is most commonly used to grow leafy greens and herbs, this includes crops like lettuce, basil, and coriander. The main characteristic of these crops is that they have a small root system, do not grow more than 2-3 ft in height, do not require trellising or support in most cases and can grow with smaller inter-plant spaces. They also do not require as much direct sunlight as other crops, in fact, basil tends to grow larger leaves and therefore more harvestable matter when grown in shady areas such as inside a structure like a polyhouse. The kinds of leafy greens that can be grown on an NFT hydroponic kit in India are divided into two main seasons i.e cold and hot weather crops. Cold weather crops include things like lettuce and bok choy when it comes to greens and thyme, rosemary, dill, and fennel when it comes to herbs. NFT hydroponics makes it easier to perform temperature control and root zone temperature maintenance with the help of external cooling mechanisms like a chiller. This is because NFT almost always has an external reservoir tank meaning the water flow can be controlled. NFT summer crops include crops like Spinach, Basil, Amaranthus, cintanella asiatica and mint that can survive 40-degree root zone temperatures. Without the use of climate control and cooling technologies, it will not be possible to grow cold weather crops in hot climates.

DWC is a method used to grow larger fruiting crops such as tomatoes, cucumbers, and gourds. Some fruits that can be grown on DWC are melons, passion fruit and berries like strawberry and raspberries. Fruiting vegetables are harder to grow than greens as they require different nutrients with varying NPK ratios to go from a “vegetative” growth stage to a “fruiting” growth stage. These plants require more complex care mechanisms and stresses in the flowering stage could cause premature ripening and fruit spoiling. The quality of fruit depends on the quality of life the plant undergoes during this phase. Fruiting vegetable containers are usually square or round and are typically 10-20L in size. Different mechanisms are used to achieve maximum aeration of roots this includes the use of bubbles in the main reservoir tanks. Some vine crops will require trellising which is a method of giving these creepers a line of support to grown and bear fruit on, this is important to avoid breakage of stems. Vine crops and fruiting vegetables also require a lot more light compared to leafy greens. Fruit bearing is a tough and testing time for plants and the reduced leaf growth during flowering has to be compensated with more sunlight Initiating the process of flowering also requires specific light cycles as well, some plants know it’s time to flower with the shorter days that winter brings. While more difficult fruiting plants can be a more rewarding experience to grow.

Location is key when it comes to choosing the crops you want to grow, Hydroponics farming in Bangalore is prosperous due to the location’s elevation and temperate climate. Winters are usually cool and summers do not shoot past the 32-degree heat. Bangalore is an ideal location to grow hydroponically throughout the year. In most places like Chennai, a grower is subject to the changing temperatures of the seasons to be able to reliably grow crops without any climate control procedures. But in the longer run hydroponic kits, crops can grow throughout the year in ideal conditions, a great technique for uninterrupted production. The added benefit of growing in a controlled environment is the low requirement of pesticides and spray based applications, these cause 90% off the residual chemicals on the food we eat. Hydroponics is the future of farming due to its reliance on sustainable inputs and removal of until now damaging farming methods.