Flushing Before Harvest – Quick Summary

Flushing Before Harvest – Quick Summary

Flushing Before Harvest – Quick Summary

1.) Wait until harvest window is almost open (how do I know when plants are close to harvest?)

How long should each type of grower flush their plants before harvest?

  • Amended Soil Growers: Don’t flush
  • Soil Growers: Flush 1-2+ Weeks
  • Coco Growers Flush: ~1 Week
  • DWC/Hydro Growers: Flush for a Few Days

More info about each one in the full tutorial below!

2.) Water plants as normal, except with no nutrients or supplements

You’re going to do everything you normally do when it comes to watering, except without any additional nutrients or supplements. Don’t give more water at a time than normal, because this increases the chances of your plants getting overwatered and showing deficiencies/symptoms caused by that problem.

3.) Watch plants closely for signs of too much yellowing 

During the flush before harvest, your plant can lose its green color very quickly. Although it’s normal to see some amount of yellowing before harvest, it’s important to harvest before the sugar leaves on the buds themselves have turned yellow. Although this doesn’t affect the quality of the buds, it does affect the appearance and buds aren’t as pretty. Additionally, once all the leaves have turned yellow your plant won’t really mature a whole lot more, and buds can start to deteriorate quickly.

4.) Harvest Your Plants

After the flushing period, your plants should appear a lot lighter than they did at the beginning. It’s time to harvest

The idea behind flushing is to let your cannabis plants “use up” any extra nutrients contained in the plant and buds. This way there is a much lower level of nutrients left over after harvest, and it’s those extra nutrients that can change the smell, taste or (most often) “smoothness” of your buds in a negative way.

So in soil or coco coir, the grower would give the plant just plain water for days or weeks before harvest time. This lets the plant use up the nutrients in the soil/coco, and then – theoretically – start leaching extra nutrients from the buds.

In a hydro or DWC setup, flushing is even easier. The grower simply replaces all the water in their reservoir with plain pH’ed water, and the plant doesn’t have access to any nutrients available except for what’s already in the plant.