Fish emulsion is organic and the one I use has an NPK of 5-1-1. The N is slowly released through microbial activity in the soil. I had forgotten to include that vermiculite is one part of my soil mix...it contains magnesium. Magnesium Mg and calcium Ca are not usually included in soluble fertilizers that are available here, and this is why I incorporate vermiculite and bone meal into my soil mix.
Wood ash contains potassium K. Potassium is also found in seaweed, granite dust, muriate of potash and sulfate of potash, to name a few. It plays many important regulatory roles in plant development: In photosynthesis, potassium regulates the opening and closing of stomata, and therefore regulates CO2 uptake.
The transplant starter solution I use does not have an NPK analysis on the label. It contains Boron, chelated Iron, chelated Mn, chelated Zinc, and Vit. B1.
During the past two years I had experimented with different soil mixes and different fertilizers and ratios. This now is my adenium culture basics: Soil mix of compost, peat moss, vermiculite, perlite, and bone meal in a ratio of 1:1:1:3:1/8. My soil mix already contains nitrogen, phosphorous, calcium, magnesium and carbon. I provide the other micronutrients using the starter solution, and also provide a periodic boost with a granular fertilizer of 10-20-20 NPK.
