Starting my first medicinal OUTDOOR crop in California. Wanted to use guanos. I have Indonesian, Mexican, Jamaican, and Peruvian (I think). The latter having higher potassium. The first 3 mentioned all have similar nitrogen ratios with little or no P-or- K (NPK). Should I just use the Peruvian since we're about to go into flower any day? mahalo DJtribes
How to Fertilize With Multiple Kinds of Bat Guano
Certified GKH Gardening Expert
Potassium is a mystery nutrient. Scientists know that plants need it to grow and that without it all of the plant's systems do not work as efficiently, but they do not know why this is. So, the Peruvian guano would be helpful for the plants in general but may not necessarily help with better blooming.
In general, with an additive like guano, I recommend that people get their soil tested before adding the guano. This is because guano is very high in nitrogen and if blooming is what you are after, adding too much nitrogen can hurt that. But, as you are harvesting medicinal plants, which tend to be grown for leaves, extra nitrogen can help significantly boost leaf growth.
Either way, you are better off getting your soil tested before adding the guano so you can see what you are starting off with and making decision on what to add from there.