It is so strain dependent no one can give you a definite answer. I've got tons of experience with Canna, and what I can say is this.
Far, faaaar more important that what you decide to give them, it is more important to be SURE what you're giving them. Invest in a great pH meter. EC meters are more forgiving, but pH is far mor critical.
If you don't know the strain, start +0.3 - 0.5 from your base tap water EC. Look at the plants daily, take pics, and really notice. If they start gowing light green/yellow, immediately up the EC by 0.2 - 0.3 EC… too much and they will "burn" - you will notice this by the leaf start tips burning.
This is "reading" the plant… even the same train, even clones… under different ambient conditions will behave differently. That is exactly why there are so many heated and dumb discussions about what is the "right" feeding schedule. The "right" feeding schedule simply does not exist!
The girls will respond to their environment. Light spectrum and intensity, CO2 levels, RH% max /min, Temps max / min, atmospheric pressure, electro-magnetic fields, orientation, water pollutants, photoperiod, EC, pH, microbiology of medium, fungal attack, virus attacks, etc etc … heck so many factors…
Just look at them, document, post and adapt, adopt, learn and improve.
General rule of thumb… start low and gradually increase. If you see stress, pull back. Adjust accordingly.
Soon, it's almost like they're talking plain english to you
Far, faaaar more important that what you decide to give them, it is more important to be SURE what you're giving them. Invest in a great pH meter. EC meters are more forgiving, but pH is far mor critical.
If you don't know the strain, start +0.3 - 0.5 from your base tap water EC. Look at the plants daily, take pics, and really notice. If they start gowing light green/yellow, immediately up the EC by 0.2 - 0.3 EC… too much and they will "burn" - you will notice this by the leaf start tips burning.
This is "reading" the plant… even the same train, even clones… under different ambient conditions will behave differently. That is exactly why there are so many heated and dumb discussions about what is the "right" feeding schedule. The "right" feeding schedule simply does not exist!
The girls will respond to their environment. Light spectrum and intensity, CO2 levels, RH% max /min, Temps max / min, atmospheric pressure, electro-magnetic fields, orientation, water pollutants, photoperiod, EC, pH, microbiology of medium, fungal attack, virus attacks, etc etc … heck so many factors…
Just look at them, document, post and adapt, adopt, learn and improve.
General rule of thumb… start low and gradually increase. If you see stress, pull back. Adjust accordingly.
Soon, it's almost like they're talking plain english to you
