What is a good foliar fertilizer for citrus that is readily available. A complete formula N-P-K plus minors.

A great number of the fertilizer formulas currently sold on the market can be used as foliar fertilizers when used at a diluted rate, such a 6-6-6, 8-8-8 etc.. However,foliar feeding should not be used as the alternative to feeding the tree through the root system. Normally foliar feeding is limited to trace mineral applications, and deficiency corrections.- Millet

I have always used liquid sea kelp as a foliar spray. Normally they tend to be in the 1-1-1 range but the real advantage comes from the 50 micro nutrients & trace minerals. Its not the best at correcting a deficiency but if used often it can prevent them. You can also include additives like neem or soap for bug prevention too.

I like KeyPlex HG:

https://keyplexdirect.3dcartstores.com/KeyPlex-Citrus-HG--32oz-_p_91.html

Best,

Skinn30a

All of the above would be good to use. A product called STEM (Soluble Trace Element Mix) sold by J.R. Peters,Inc. is the inddustry standard used by nurseries, orchards, and greenhouses for both foliar application and root absorption, for applying trace elements. Again, I would advise you to apply NPK through the soil. - Millet

I've used KeyPlex in some trials on nursery crops and a couple of other horticultural crops. By itself, it wasn't very impressive. When added to another foliar product, such as 20-20-20, it increased the growth substantially compared to either product alone. The KeyPlex rep also mentioned that it gave the plants "acquired systemic resistance" to certain diseases. The other good thing about it was that it is a byproduct of the beer brewing industry. So less wastes from that industry.

An easy find in a garden center would be miracid 30-10-10. It also contains many micronutrients.