I’m not an expert on fertilizer and I don’t use any liquid fertilizer, but 0.2-0-0 seems too low to me. I usually go with a citrus fertilizer with micronutrients. There are both synthetic and organic options available.
I do mix them both - spinosad and mineral oil. I followed the video here. I think @hoosierquilt suggested adding neem oil to the mix. So, I replace 50% mineral oil with neem oil.