As you would expect with a traditional garden, a hydroponic garden also requires control of pests and diseases. Overlooking this aspect can result in a crop of dead plants. Since the majority of hydroponics plants are fruits and vegetables, that means: plants not worth eating.
But the situation with hydroponics is even trickier, since disease and pests have it much easier in this setting. This is because hydroponic plants are being constantly kept wet, either via water immersion, or by being sprayed, or even via a wet soil like perlite or sand. Fortunately, as with soil-based gardens, there is an array of techniques available to manage the problem.
Using beneficial organisms is one popular way to control unwanted pests, including certain types of bacteria and fungi. They can aide with control of pests like spider mites by either releasing toxins into the plant, or simply by eating them. They’re called beneficial because they do all that without damaging the plants themselves.
There are different types of pesticides available as well.
One example dating all the way back to the 18h century is the use of pesticidal soaps – as old as the technique is, they still provide an excellent defense against pests. Botanicals are a sub-category of this. They are made up of compounds that have been released by the plants themselves, then captured and packaged for ease of use. Because botanicals are natural, the break down easily and leave no harmful chemicals behind.
Neem oil is another option, which helps to control over 400 types of invasive bugs. A simple spray to the leaves can often eliminate common pests. The bugs absorb the oil, which interferes with their ability to reproduce, leading to a lower population.
If the infection is serious, there are many commercial pesticides available.
Pests like aphids, mites and white flies are an issue for hydroponics gardens just like with traditional gardens. Powdery mildew is a common problem. As a hydroponic environment is very moist, mildew has the chance to thrive is not treated. Making it ‘unfriendly’ is easy though, using fungicides and organicides. Sulfur-based compounds help control white flies, mealy bugs, thrips and more.
Another commonly used solution is Pyrethrum. It my sound scary, but the product is made from flowers. This class of natural compounds released by plants are extracted and used in many commercial insecticides. As dosage is low, the compound is safe to use, when used correctly. Azatrol is another option as is provides a solution for a wide variety of common pests.
As with any garden, a hydroponics gardener needs to be careful with use of any pest or disease control.
It is easier to damage the plant when moving the stems and leaves as there is no soil present to secure the roots. If for example you are picking mites off the plant by hand, extra care must be taken as not to damage the plant.
Since moisture is present, mildew and other fungi are more common. Keeping it so that just the roots are wet should help. Allowing any sprayed on insecticide to dry under the lights is recommended. This may mean that plants will have to be temporarily relocated is they are aeroponically grown.
