What’s pH and Why is It Important?

While growing your own can be a walk in the park, you need to know a few more things before you get started.

Like pH. These two little letters are more important than you might think. pH is the acidity or alkalinity of something. It actively affects how well your plants take up nutrients and minerals, and how readily available they are to your plants.

What is pH?

Think of pH as temperature, and acidity and alkalinity as hot and cold – they’re two extremes, except pH describes chemicals. The pH scale ranges from 0.0 to 14.0. with 7.0 being neutral. Anything below 7.0 is acidic and anything above 7.0 is alkaline (or basic).

For example, 4.0 is 10 times more acidic than 5.0. This also means that 4.0 is 100 (10 x 10) times more acidic than 6.0 and 1,000 (10 x 10 x 10) times more acidic than 7. Note that we included the decimal points for the pH values we mentioned above. Because the concentration of each pH value increases tenfold, the decimal points are crucial. Even a difference of 0.3 could drastically affect your plants!

How does pH help my plants?

Depending on what the pH is of your plant’s growing medium, it can really affect how your plant absorbs nutrients. If what you grow in is too acidic, your plant will most likely wilt and die because it can’t absorb nutrients. In the same way, if what you're growing in is too basic, your plant will suffer the same fate.

If you’re using soil, most plants prefer a slightly acidic pH range, between 6.0 and 7.0. If you grow in a soilless or hydroponic system, then the ideal pH range is 5.6 to 6.2.

Soil vs. hydroponics

If you’re using soil, you should be using a good mix of soil that contains an assortment of nutrients.

The soil can actively slow the change of your pH range, if your plant experiences any changes in its growing environment.

Sandy soils are more acidic, clay soils are more basic, and woodland soil is more neutral. Anything that you add to your soil can affect its pH – additional nutrients, rain vs. hard vs. clean water. You can test the water that you use by testing the run-off water, which will give you a better idea of your plant’s pH as well.

If you have a hydroponic system, you’ll need to add your own nutrients, which means you’re directly controlling the pH levels. They will change faster because you have no buffer. These fluctuations will occur naturally thanks to your system’s reservoir.

You’ll also have to monitor the pH of your system to make sure you’re not making it too acidic or too basic. Its range should be between 5.5 and 6.5. You can adjust pH by using pH Up (such as Potassium Hydroxide and Potassium Carbonate) and pH Down (such as Phosphoric Acid) solutions.

BC Northern Lights offers premium nutrients and all the necessary equipment to ensure your grow system has an optimal pH range.