In the past week I´ve noticed my plant has like drying little spots in some leaves, the tips of some leaves are drying out too. I´´ve noticed also that some leaves (the biggest ones), have a different, lighter colour in the middle than on the edges. Are those bad signs? I´´ve been looking for bugs and didn´t find any, so I suppose the very high temperatures and the so intense sun light is causing that. Could I be right?. What can I do to avoid all these?
overfertilization - i.e. fert burn. need to flush your plants ASAP with plenty of water. but it could be heat stress, but that usually affects the portions of the plant closet to the lights.
u can also go to www.canna.nl. This site is also available in english. When u enter the site u have to go to growinfo and then to info courier. U can see with the pics and the writing what it is that u r plants need and what u should do. They are probably missing something that the leaves got like this. like magnesium,calcium or nitrate or something like that. But u can see that for u r self.