Fertilizing Q

Hi people!
I'm new to all this stuff so please don't mind that questions are very unprofessional.
i have plants from seeds for about 6 weeks in soil. They look really good. Can you tell me when should i fertilize them with blooming solution canna PK 13/14?
Also question - maybe i should use some other food in addition like plagron grow?

thaks!

you should have something to give to it now like something with n, and then when you start flowering use pk 13/14

Hi Desr, i have Canna Start which is for young plants but it might be ok?