How do you maintain pH balance in hydroponics?

Hydroponics is a technique of cultivating plants without using soil. Instead, the root system is propped using inert agents such as rockwool, pellets made of clay, perlite, etc. and the nutrients are made available using water-soluble mineral nutrients. The rationale behind this is to allow the roots of the plant to directly access the nutrient solution and atmospheric oxygen, both crucial for plant growth and sustenance.

Why use hydroponics to grow things?

Since hydroponic plants have their roots directly accessing the nutrient solution, they do not need an elaborate root system like conventional plants to get their nourishment. Instead, they can use the saved energy on nurturing their leaves and stem. Also, since the root system is small and confined, hydroponic plants take up less space, and more plant growth can be seen over the same area as compared to non-hydroponic plants. Moreover, hydroponic plants report faster growth owing to the absence of soil-residing pests. Ample access to oxygen further rejuvenates hydroponic plants as oxygen helps in the swift absorption of nutrients, thus boosting plant growth. Hydroponics is an effective and ideal option for growing plants in limited spaces.

Role of pH in hydroponics

pH or potential of Hydrogen is a measure of how acidic or basic a solution is (using best pH meter for hydroponics), it calculates the concentration of hydrogen ion in a solution. pH helps in determining the solubility of nutrients in a water-based solution, thus affecting the mobility and uptake of nutrients in plants. An ideal pH for hydroponic plants resides within the range of 5.8 to 6.8, with a pH of 6.3 being considered optimal. If pH is too high or low, plants cannot absorb and uptake certain nutrients and will show deficiencies, while there will be certain nutrients that will be heavily absorbed leading to toxicity. Hence, it is inevitable for hydroponics to maintain the desired pH levels.

Maintaining pH in Hydroponics

Maintaining the pH of hydroponics can be done using pH-Up and pH-Down solutions. pH-Up solutions are used to raise the pH level and pH-Down solutions are used to lower the levels of pH. Generally, acids-based solutions are used to lower the pH and base solutions are used to raise the pH.

A common choice for a pH-Down solution is phosphoric acid, while potassium hydroxide is a useful pH-Up solution. These solutions when used, should be allowed to diffuse and disseminate properly before re-administering them. For organic hydroponics, domestically used citric acid can be used as a pH-Down agent. Other options for adjusting pH include sulfuric acid and nitric acid, both of which can be effectively used as pH-Down solutions; however, they are more hazardous than phosphoric acid.

There is also the option of using domestic ingredients such as vinegar as a pH-Down and baking soda as a pH-Up solution. But household solutions do not help in the long run as they lack the pH buffer present in commercial solutions. Automatic pH controllers do an excellent job of sustaining pH to optimal levels; however, they are not cost-effective compared to pH-Up or pH-Down products.

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