I have found neem oil is well tolerated on some plants, but damaging to others. Neem oil appears to work well on the broad tougher leaf plants. On the other hand, it burns my ferns and shrimp vines. It should be noted that shrimp vines do not like any foliar spray, even 💦 water. I use a cold pressed variety of neem oil that I must place in the microwave to transform the oil to a liquid state. I heat my water until it simmers. I then take the neem oil and heated water and place it in the blender at the highest possible speed. This will give you properly emulsified neem oil. I believe proper emulsification is critical to obtain an even application of the neem oil solution. If you are unwilling to take these steps, it is better to use the pre-emulsified mixture. if you are fighting fungus gnat, I prefer mosquito bits. However, if you are dealing with a whitefly infestation, mosquito bits will do nothing. In my view neem oil takes a while to work and is not tolerated well by all plants. I try to use it as a systemic poison, but this method takes time. For the broad leaf plants, I prefer to use a dormant oil as a wipe. Unfortunately, it has been my experience that no one thing is a solution for all manner of pest control. Some people swear by cinnamon. Some people swear by diatomaceous earth. And then there are others who prefer insecticidal soaps. Dormant oil has its fans, but like neem oil, can damage foliage. Whatever you do invest in some sticky traps. They are non-toxic and yummy tasting to your pest(s). They are attracted to the yellow color. I wouldn’t be without them since you may think an infestation is gone, but after a few days you will see if you’ve cured the problem. You will also be able to correctly identify your pests. After you’ve identified your pest call the best grower/greenhouse in town to determine their specie recommendation for the treatment of African violets. You may want to glean more than one opinion. I’d suggest your state’s extension agent, but there expertise is more towards commercial growers than indoor hobbyists such as myself.

Neem has the active ingredient azadiractin, which is an insect growth regulator. I took a look at the link you provided and it looks like there is no azadiractin in it. They have converted it to something similar to insecticidal soap, which also is potassium salts of fatty acids. There are many fatty acids, so not all products listing this ingredient are the same. The website suggests that this is more effective than regular insecticidal soap ("This unique fatty acid profile provides K+ Neem with exceptional insecticidal, miticidal and fungicidal properties.") because it is derived from the neem tree. Unless they have tested the product in a side-by-side comparison, there is no basis for this statement. I am also skeptical of the statement "because the mode of action is mechanical in nature insects and mites do not build up a resistance". There is no reason why insects can't develop resistance to this product. The bottom line is that this product is not what usually is sold as Neem. If that is what you want, then you need to look elsewhere.

Neem Oil is a natural product and very good for use as insecticide, but caution on when and how to apply is needed. This caution is same with many insecticides. Never used as fungicide, but it does state on Rob's photo of product. For Cuts, it is not necessary to treat with exceptions to large branches or roots. Cuts on branches should be made at a 45degree angle. I paint the ends of my pruned branches with Elmer's Waterproof Glue ( a product that my friend Laura got me onto. Love it. ). I would use Sulfur on roots, the product that Rob has posted. Let dry before planting. Rick

the concentrate lists 70% neem and 30% other, so I wonder if it has emulsifier in the 30%? As a side note, I also wonder why you can have a RTU neem product, whereas when you mix from concentrate, the product degrades within a short time frame?