Question about the NPK in fertilizers
Firstly apologies for all the questions on the forum recently. I am new ish to gardening and there are questions I have but I can't find the answers online.
I want to grow a clematis and I saw a video from crocus.co.uk that you should add bonemeal to the planting hole. They said bonemeal promotes strong roots and more flowering as it is high in phosphorus. I also read that postassium promotes strong flowering in things like fruits and roses and that they should have a high potassium fertilizer.
So what is the difference between phosphorus and potassium? If they both promote strong flowering, why use one over the other?