This is an updated and revised article as of 22/07/20
Recently at A-Grade Hydroponics we have observed a massive number of new growers and customers wanting to switch from their current brand of nutrients to another one in the middle of a crop cycle.
(We don’t sell all nutrient brands, as we don’t believe in just selling stuff because of a fancy label. We, and our customers, want results.)
What can I do so I don’t have any major interactions when starting a new nutrient?
Great question, the answer is this:
When you are feeding your plants using a run to waste style growing method, we make a solution that is perfectly pH balanced and the EC content is relative to the plants current size and growth rate. The benefits of a run-to-waste (drain-to-waste) is so all the elements required for growth are always present without depletion and depletion only occurring in the time between the next feed, this will produce optimal results.
As the root zone grows, so does the plant. Run-to-waste feedings have to change accordingly, some growers do not alter the volume of solution in conjunction with the plants consumption, the result is less run off is achieved. When less run off is achieved and the plant is consuming food and water, this may result in a build up of excess salts in the medium due to a lack of water, which if un-flushed can cause things like nutrient antagonism, root problems and elemental toxicity.
So, when changing over to a new line of nutrients, it's a good rule of thumb to flush your plants first. The flush must be pH balanced for best results.
Once you can ensure that you have removed the majority of the nutrient buffer from the medium, a quick check of the EC & pH run off should confirm the pot or system is no longer holding any excess nutrient.
The following day you can resume feeding with the new nutrient line chosen, we generally recommend the grower start 25% less than recommended simply to not antagonise any elements, approx. 3 days later we can go to full strength and follow the chart and dosages given.If you do want to change over and you are unsure, call or email us and we can help you as needed.