Tank mixing is defined as mixing multiple chemicals together in one tank. By giving growers the ability to do just one application vs multiple applications during the week, tank mixing can save time and, as any successful greenhouse operation knows, time (i.e. labor and fertilizer application costs) is money.

But tank mixing (sometimes known as ‘bucket chemistry’) without checking the compatibility of what you’re mixing can cause serious problems that, in the long run, can wipe out all time and cost savings and seriously negatively impact the other main factor in a successful greenhouse operation: increased plant yield. Whether you grow ornamental flowers, vegetables or cannabis plants, in this article, Plant-Prod will share what can go wrong with tank mixing and 4 tips on doing it correctly.

Done incorrectly – or more specifically, incautiously – tank mixing fertilizers with other chemicals can wipe out your cost savings and hurt your plant yield two ways:

  1. Biological incompatibility: The biological incompatibility of different compounds – whether they be your fertilizer, pesticide or even your water – isn’t always readily apparent but, if not checked carefully can do immediate damage to your plants or impact them in the longer term by reducing the efficacy of your fertilizer nutrients.
  2. Physical incompatibility: Mixes that don’t dissolve, that precipitate or separate can clog or even completely halt your sprayers and irrigation lines or have you & your team spending too much time cleaning out the bottom of tanks, wiping out the very time savings you were hoping to achieve.

Tips to tank mixing water soluble fertilizers 
If there are still times when you want to tank mix, here’s some steps to doing it successfully.

1. Skip it by using an all-in-one water-soluble fertilizer

Plant-Prod has a wide variety of completely water soluble formulations designed to provide the micronutrients your plants need in the same single tank eliminating the need to tank mix.

2. Always check the label

Most fertilizer suppliers will tell you how to mix or whether there are restrictions with other compounds. 

3. Conduct a jar test

A simple way to check physical incompatibilities is to take a clear container, use the same water you would normally use, add the compounds, agitate them, shake the jar and observe to see if you have any unusual chemical reactions or physical incompatibilities. 

4. Live Test

Try the compound on a small group of plants – or different species if you grow multiple flower or plant species – and monitor over time for adverse effects or reduced yield.

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