"Malfunctioning fertilizer injectors can compromise your spring crop"

A frantic call from a grower late last week reminds me to encourage all growers to check their fertilizer injectors before entering the hectic spring growing season. A malfunctioning injector can add on weeks to your production schedule, reduce crop quality, or even “kill” your plants. While this may seem like an exaggeration on my part, my work in central Pennsylvania has shown that “75% of the fertilizer injectors employed by growers in area greenhouses are not working properly”.

written by Thomas Ford

Most growers tend to take this critical piece of equipment, (the fertilizer injector) for granted, but the constant exposure of the O-rings to the various chemistries in the stock tank during the growing season tends to impact injector performance over time. When an injector malfunctions, it typically does not inject the appropriate quantity of fertilizer stock solution into the irrigation water. When the amount of fertilizer solution injected into the irrigation water is too low, the EC of the growing media drops which signals a less than ideal level of nutrients in the media that are available for plant growth. In the case of acid injection, a malfunctioning injector will typically inject an insufficient amount of sulfuric acid into the irrigation water resulting in a higher nutrient solution pH that ultimately causes a gradual rise in the media pH leading to micro-nutrient deficiencies as depicted in the photo of the Fe deficient calibrachoa basket.

When an injector begins to malfunction, a grower may be perfectly oblivious to this event unless they are testing their injector output on a weekly basis. In most cases, growers will only discover an injector is malfunctioning when the crop that they are growing begins to display foliar symptoms. As spring shifts into high gear, please take the time to check the calibration of your fertilizer injector so as to insure the health and vigor of all of your horticultural crops.

Source: eGroBlog