Major Factors to Consider in Hydroponic Plant Production

HydropanWhen growing plants in a hydroponic garden, we must consider the following factors.
  • The amount of water the plants need; proper drainage of growing medium
  • The optimum temperature and light for the plant
  • Fresh air
  • Shelter and support
  • Pest and disease control
  • The water-soluble minerals the plant needs
  • The proper pH of the nutrient solution


As with all plant needs, the amount of water required depends on the plant species and the needs of that particular plant. A plant that suffers from lack of water will extend a huge, but not very effective, root system and will develop a very small plant above the ground. As a result many roots are sent out in search of water and unless an inadequate supply is found, the plant will not grow to its potential.

At the other extreme, if a plant is over watered, the roots can drown, because they are not receiving the proper amount of fresh oxygen. This makes proper drainage of a hydroponic growing medium absolutely crucial to your plant's health. The correct setting of your pump timer, according to your particular conditions, will ensure your plants never have too much, or too little water.The last consideration concerning the water you feed your plants, is purity. In a hydroponic garden, you should use the purest water possible. Water that has possible toxic contaminants or salt build-up may stunt or kill your plants. Your municipal water is good enough in most circumstances. Rainwater is preferable

Temperature and Light

The ideal temperature depends on the crops you choose to grow. Most of the common garden crops, such as tomatoes, cucumbers, beans, spinach, beetroot and herbs, will do well with an average daytime temperature of 26 degrees C and an average night time temperature of 21 degrees C. Winter vegetables, such as cabbage,brussel sprouts, lettuce and broccoli, should be grown in slightly cooler temperatures.

A minimum/maximum thermometer will allow you to track the high and low temperatures in your growing environment. The use of a shade cloth or horticultural plastic greenhouse, will help to regulate the environment surrounding your garden.

Fresh Air

Plants require adequate air circulation around the plants, as well as proper aeration in the root zone. Poor ventilation in the growing environment encourages mould, mildew and plant disease. Many hydroponic gardens are located off the floor, for better air circulation. Commercial hydroponic greenhouse growers use large fans and air circulation equipment to provide adequate air movement.

Shelter and Support

In a commercial application, many hydroponic farmers grow their crops inside a controlled environment greenhouse or tunnel. This not only provides shelter, but also an ideal, stress-free environment for the plant. Because many hydroponic gardens are quite small and very clean, they can be set up almost anywhere, indoors, on a patio or a windowsill, making it easy for the gardener to provide shelter for the plants. In a traditional garden, the soil anchors the plant and provides support. In hydroponics, the growing medium helps support the plant to some extent, but in some situations additional support is needed. Plant stakes, strings, and clips are used for this.

Pest and Disease Control

Since there is no soil in hydroponics, many, but not all plant diseases are eliminated. Well-kept and clean growing environments are the best prevention when it comes to plant disease. Always remove dead or dying leaf matter, and any unhealthy plants, from your hydroponic garden. The single most prolific problem encountered in the hydroponic garden is the growth of algae in the system. This can be remedied by adding a hydroponic disinfectant to the water. Various remedies are available for combating other pests and diseases found in the gardens.

Water-Soluble Minerals (Nutrients in Solution)

As mentioned earlier, a hydroponic gardener uses minerals that are water soluble and ready to be taken up by the plant roots. Scientists and researchers have determined exactly what minerals a plant needs and in what quantities. A large number of hydroponic nutrient formulas have been developed and, although some have better results than others, there is no one perfect mixture. The success of each nutrient formula depends on the conditions it is used in and what plants are being grown.

Many hydroponic gardeners use a pre-mixed nutrient formula, that they simply add water to. These formulae's contain all the minerals and nutrients that a plant needs, in the correct proportions and are available in powder or liquid form. Hydroponic Concepts™ have a two-part, pre-mixed, granular nutrient range, available for use in our systems. A general granular feeding program is provided with each garden, to assist you in mixing the nutrients.

The concentration of nutrients in a nutrient mix, is measured by measuring the electrical conductivity or (EC) of the mix. Therefore nutrient concentrations in the water are measured by using an electrical conductivity or (EC) meter. The general granular feeding program allows you to prepare a nutrient mix, without the need for an (EC) meter. However, for better growing results, an (EC) meter can be used, in conjunction with an advanced nutrient program.

The macronutrients a plant needs include:
  • Nitrogen
  • Phosphorous
  • Potassium
  • Calcium
  • Sulphur
  • Magnesium
  • Iron
And the trace elements (used in minute quantities) a plant needs include:
  • Manganese
  • Boron
  • Zinc
  • Copper
  • Molybdenum
Proper pH

pH is the measurement of the hydrogen ion concentration in a particular medium, such as water, soil, or nutrient solution. More simply, it refers to the acidity, or alkalinity, of that medium. pH is measured on a scale ranging from 0- 14, with 7 being neutral, above 7 is alkaline and below 7 is acidic.
The pH of a medium, or nutrient solution, is important to plant growth. Each plant has a preferred pH range.
pH ranges beyond that which is preferred for a given plant, may cause stunted growth or even death. A preferred general range for hydroponic plants is, between pH 5.5 and pH 6.5, with the ideal at around pH 6. A prolonged pH below pH 4 and above pH 8 will cause damage to plants. The general granular feeding program includes information on how to adjust the pH. The adjusting of pH is not always necessary, as the hydroponic nutrients have an acidifying effect on the water. In many cases, once the nutrients have been mixed with the water, your pH will be well within the acceptable range.