Hydroponic nutrient solutions are one of the most important things to consider in hydroponic gardening.
Get it right and you will be rewarded with a bountiful harvest of your chosen fruits.
Get it wrong and be prepared for great disappointment and a poor yield.
Your nutrient solution must contain the correct amount of nutrients as well as other additives that are naturally be found in soils. All are vital to ensure a plant’s growth and its resistance to pests and diseases.
What Kind of Water To Use In Nutrient Solutions
Usually a nutrient solution is made from fresh tap water. There is generally no need to use any type of filtered or bottled water unless you don’t have access to clean fresh water or your pH level is totally off the scale and unmanageable. Good quality nutrients are usually pH buffered as well. This means that once you have mixed your nutrients into your water, a small amount of adjustment with either pH up or pH down on a regular basis is all that is needed.
Prepping Your Water
If you can, fill your reservoir with fresh water and allow it to stand for 24 hours before you mix your nutrients. This is advised because it allows time for chlorine and other chemicals found in fresh water to disappear. Allowing the water to stand for a day makes it easier to calibrate your pH…but this is not always possible, especially if you have a large reservoir. If you have the time and space, letting the water sit will benefit you.
How Often to Adjust pH of Your Nutrient Solution
If you are using a passive hydroponic system like the nutrient film technique or flood and drain, chances are that the pH will need adjusting every 1 to 2 days to keep it at the optimum level. Plants prefer fresh water so it’s advisable that the solution is totally drained and replenished on a weekly basis. Although this can be time consuming, it is golden advice given to me from a very experienced hydroponic farmer.
A weekly change of solution can mean all the difference to the final yield and is well worth the effort. Flushing or leaching of the system in the last week before harvest is also worth the effort. Flushing will give the plants time to lower the potential build-up of salts and minerals that will have accumulated during growth which can affect the final taste of the produce. This can be done by lowering your total PPM to 1/3 of its normal strength for the final week before harvest. Most hydroponics shops stock a good quality final flush.
Benefits and Problems of Automation
With some hydroponic systems, automation of the feeding cycle can be a blessing but also a hindrance. Most systems use a pump of some type to deliver the solution to the plants which can save time on watering but can also be problematic.
It is advisable that the plants are always allowed access to the solution. Letting them go thirsty can cause stress and slow down growth. Unlike soil bound plants that can draw moisture from the soil around them, in hydroponics once the circulation is stopped the root system can become dry quite quickly, especially in indoor environments and hot climates.