Hydroponic gardening is the technique of growing plants without using soil in a nutrient media which is hydrophilic in nature. So as the definition says, nutrients are practically the backbone of hydroponic systems. Without basic nutrition, a hydroponic garden will have no chance of survival. Since there is no soil which can act as a source of nutrients, the medium in which hydroponic plants are growing should contain accurate amount of minerals, vitamins, and primary, secondary, and trace nutrients.
Accuracy of nutrients in hydroponics systems is important because otherwise every stage of plant growth will be affected if there is even slightest deviation in amount of nutrients. The desired end results like good yield, blooming flowers, green vegetables, and juicy fruits can be achieved only if you provide the hydroponic nutrients in a precise quantity. The need of nutrients will keep changing constantly throughout the growing process. All the grow phases require monitoring and proper care.
Every plant has its different need of nutrients and you have to mix up the solution accordingly. For example, leafy vegetables thrive on minerals where as flowering plants like lilies and roses grow best when provided with potash enriched nutrient medium. Here are some of the basic nutrients required by most of the hydroponic plants and the effects if they are not provided in accurate quantity:
Nitrogen: It is one of the most essential elements required for healthy plant growth. If your hydroponic system fails to provide precise amount of Nitrogen to the plants then the leaves will turn pale green, or perhaps even yellow in cases of more extreme nitrogen deficiency. Also growth of the plants may get stunted. In case of excessive Nitrogen provision, your roots may become stunted and cause a delaying in flowering.
Potassium: Hydroponic nutrients with less amount of potash will lead to blackening of leaf edges. Also the fruits which grow in Potassium deficient medium will be lighter in weight than normal ones.
Phosphorous: Deficiency of Phosphorous will lead in smaller roots, stunted growth, and reddening of leaves. Sometimes you may observe that even if your hydroponic nutrient solution has enough amount of Phosphorous, plant growth is stunted. This may be the result of your solution being too cold as this decreases uptake of Phosphorous by the plants. Maintain nutrient solution at room temperature.
Micronutrients: Elements like Calcium, Magnesium, Iron, Copper, and Manganese even if are required in very small quantity, should not be neglected. Deficiency of these elements will lead to yellowing of leaves, dead spots on the older leaves, mutation of plants, and adverse effect on overall growth of plants. Make sure your hydroponics nutrient solution has just the exact amount of these elements in it.