Q.Yellow Leaves on Winter Greens
I’ve Been getting these yellow leaves recently with my kale and spinach. I’ve been consistent with fish emulsion for nutrients once a week. What else can I do to stop nutrient deficiency? Do I need to add manure to top layer of my soil or worm teas?
Certified GKH Gardening Expert
Fish emulsion will be, mostly, nitrogen. This deficiency will appear on the newest leaves first.
Because of the high nitrogen content, a weekly feeding may bring the soil to be too acidic. This can lock out phosphorus and potassium, as well as calcium and magnesium.
That looks like the classic symptoms of a magnesium deficiency.
I would add a simple handful of DOLOMITIC LIME per container. This will help to correct the issue.
In the future, I would make sure to test soil EC (electrical conductivity) which will tell you the nutrient content, and the pH before adding nutrients to make sure that there isn't already enough or too much.
Alternatively, you can do a dropper test, which can tell you some of the same information. This article will help: https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-soil.htm
This article will help you to grow winter greens: