Grow Q&A: How Do I Know When To Flush My Pot Plants?

Dear Dan, My problem is not knowing when I am two weeks from harvest time, so that I can quit nutrients and flush with plain water. I have no reference to know how long it will take to go from clear trichomes, to milky white tirchomes. Or how long it takes to go from all white pistils to 25 percent red pistils? They say that for White Widow, the flowering period is 8 to 10 weeks.  Is that from 12 hours on/12 hours off, or from when the first actual flower appears? – Vincent

Dear Vincent,

The flowering period begins from the moment you switch the light cycle to 12 hours on/12 hours off. So, for your White Widow, you should begin the 2 week flushing period at between 6-8 weeks based on your listing of it being ready to harvest at 8-10 weeks. Even if you err on the side of caution and begin the flushing process a week too early, it’s not the end of the world. You’ll simply have a little bit longer of a flushing time and may experience fall colors on your leaves but the end result will be a cleaner burning product.

Buds are ripe when the trichomes go from mostly clear to mostly cloudy with some amber ones. Don’t worry about the colors of the pistils (or hairs) because they aren’t the most reliable way to determine when to harvest your plants.

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(Photo by Chiefer420)

1 comment
  1. Why aren’t the pistols a good way to tell when it’s ready to harvest? My scope is broken and that’s how I’ve been having to do it for awhile. What’s the best way to eyeball it? And what happens if it goes a week or 2 past cloudy with some amber trichomes?

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