Q.Ratio Of PH To PPM For Hydroponic Spinach
I’m experiencing difficulty with hydroponic spinach (stunted growth,leaves curling under,spots on leaves,weak roots that were too far from solution) & am replacing solution in DWC tank. I want to try half strength solution to see if plants will recover. Current pH level is 6.56 & PPM 715. The chart I have recommends pH 5.8 – 7.0 & PPM 1260 -1610. I know pH & PPMs must coordinate in order for plants to absorb nutrients. Does this matter short term or do I need to up nutrients while I wait to see if the plants do anything?
Certified GKH Gardening Expert
Well, sort of...
The pH must be within range, AND the nutrient concentration must be within the parts per million range for the specific needs of the plant at the specific stage of the plant's life.
In this case, the spinach would be fine at around 300-500 ppm. They really don't need that much nutrients, and will start to taste "off" the more that they receive.
Your problem is an infection. This could have been from an insect feeding, or from general water infection. Either way, this will need to be started over.
Make sure to sterilize the tub before you use it again, or it'll end up doing the same thing.
Here is an article that will offer more information on growing spinach in this fashion: