To Flush or Not to Flush

Should you ditch the nutrients during the final stages of your plants' growth?

What, Precisely, is Flushing?

It takes place around the last two weeks of the grow cycle although it can also be done midway through, especially if overfeeding has taken place. It is most often done just before the flowering stage and will help to optimise the NPK (nitrogen, phosphorous and potassium) ratio.

In theory it also makes your plants process all of the nutrients that they have absorbed which as a result means there is a lower nutrient volume and less potential contaminants in the final yield.

Any Doubts?

There are several.....

Some believe that panic can arise, meaning the system is flushed too hard and that it leads to nutritional deficiencies.

Others believe that the option of flushing leads to overall laziness during the growth cycle, and that regular EC checks and feed level checks should be carried out.

'Blind-Tasting' has even been carried out, where a recipient will be asked to compare flushed and unflushed products and it is claimed that there is little or no difference in taste.

And the ultimate claim is that a plant should not be deprived of any nutrients at any stage.

Any Support?

Those in support of flushing will ask.... if plants absorb nutrients then how can flushing the system deprive them of them?

In addition to this, flushing out the system will actually encourage the plants to utilise the nutrients that they have already absorbed. It also means that there will be less chemical remnants attached to your plants that haven't been fully absorbed.

Stress on the plants actually brings about a positive outcome as the late deprivation of nutrients forces them to adapt and enhance their own natural defences.

Overall it is felt that flushing reduces excess salts and nutrients, balances the NPK levels and promotes growth.

Pre-Flush Nutrients

The truth lays somewhere between the middle of both arguments and one thing to be embraced is a pre-flush nutrient. A great example of this is the final flowering booster from Shogun known as Dragon Force

This uses sulphur and sends a signal to the plant to make a final push for growth. It also stimulates the plant's defence systems and enhances the production of resin and aroma compounds.

Using this for ten days, followed by four days of flushing, will speed up the process of maturation and forces faster ripening and gives an all-round bloom of higher quality.

The Right Balance

Overflushing can definitely steal some nutrients from your plants so don't do it too soon and don't overdo it. Too much can reduce the flower growth and resin production.

Find the right balance with a little bit of experimentation and a little bit of flushing will certainly help your harvest.

These flushing products from Canna and Plant Magic are recommended and the video below from Shogun gives some great insight!