The truth about flushing before harvest

The truth about flushing before harvest

Flushing plants in the period before the harvest is a well known habit for many growers. But there’s a lot of discussion about it. How do you flush a plant? Does it work? Is it necessary at all? We’re going to bust a couple of myths.

How to flush plants?

Flushing your plants means giving them much more water than usual, without nutrients, for a period before the harvest. According to pro-flushers this rinses unnecessary nutrients out of the substrates and purifies the plant before harvest. There’s a lot being said and written about flushing and the different ways to do it. Some sources you should flush for two weeks and others for only one week. Some state you should water as usual and others say twice as much as usual.

Is flushing necessary?

Ask a group of growers about flushing and you’ll quickly see them divided in two camps. Here’s the kicker though: there is no scientific research that proves flushing has any effect. Nutrient concentrations in a flushed plant aren’t demonstrably lower than in unflushed plants. Besides, it’s not sure if you would even want that. Nutrients aren’t bad for humans and it’s hard to prove that can be tasted in the harvest.

Flushing is bad for quality?

Many growers are strongly anti-flushing on the other hand. According to them, flushing has bad effects on the quality of the harvest exactly because the nutrients are rinsed out in the last critical week. Again, if you look at recent research, there is no proof for this statement. However, long periods of flushing can be bad for your plants as a whole. It can cause root rot and make your plants vulnerable to fungi.

To flush or not to flush?

It’s simple, really. Flushing has no probable positive or negative effect in the quality or total yield of your crop. It can have a bit of an effect on your bank account, though. If you don’t fertilise for a week of two, you can save some money.

Whether you want to flush or not is ultimately up to you! Do you believe it helps? Then do it! If you think it’s nonsense, don’t. We can only tell you what scientific research has shown. Would you like to know more about flushing before the harvest? Our Servicedesk is there for you!


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