It's very simple, that chart is rock solid. It leaves room for experimenting with other doses or even adding other supplements in the future.
Feed at the doses in that chart, every watering.
If your medium has nutrients in it and depending on how much, feeding might not start for 4 weeks.
In a medium like Pro-Mix HP (no nutrients in it) you would start feeding around 7-10 days.
This is where I found that feed chart, has other good info about the Flora series in it.
For many people, nutrients can be a pretty confusing topic. Not only are there tons of companies to wade through, but some companies have multiple nutrient lines, extra supplements, additives, etc. And once you’re through with that, you still have to figure out how much and how often to feed...
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