Water-Insoluble Fertilizers and a Foliar Feeding

I’ve been doing some research but I cannot seem to find the answer to this question: can and/or should you foliar feed with fertilizers that have water-insoluble elements?

My understanding is that “water-insoluble” suggests that the element needs to be broken down in order to be available and used by the plant - otherwise known as slow-release. This would seem to me then that such fertilizers would not be efficient in the context of foliar feeding since the stoma requires readily accessible nutrients and does not have the capacity to break them down.

The reason for my question is that I purchased a fertilizer - Nitro Big - that contains 7% water-insoluble organic nitrogen. The label provides directions for foliar feeding but I want to make sure I’m not just wasting the nutes, my time, and possibly harming my plants if I spray with it. Any assistance in better understanding this issue is greatly appreciated. Thanks!

Foliar feeding isn't necessary and I've seen beginners completely torch their plants from foliar feeding.

That certainly makes sense. As I get further into my first grow, it’s becoming more and more apparent that there are techniques which are better suited to more experienced growers - HST, foliar feeds, ect. Ultimately, I may just scrap the idea of foliar feeding completely. But since I already have the nutes and I won’t be a first time grower forever, I’m just trying to get a better understanding of foliar feeding as a technique in cultivation. My hangup right now is just figuring out whether one should or shouldn’t foliar feed with fertilizers that contain water-insoluble elements. Thanks.

I like using liquid kelp for foliar feed, it helps reduce stretch and the plants seem to love it