Container pH level?

[barryla61]

SWC's not included.
What do you consider the optimum pH level for regular container mixes?

[Crandrew]

6.5, dont worrying so much

[artis]

6.5 is perfect, 5.5-7.0 is fine.

If you use tap water for watering, pH may become a significant issue. Where I live, pH of tap water is around 8.0. Plants suffer from nutrient defficiencies at pH 8. The problem gets worse later in the season because pH in the pot keeps going up from using the tap water.

[fortyonenorth]

The reason we manage pH is to maximize availability and minimize toxicities of nutrients. 6.5 is a "sweet spot" for in-ground growing, but I would shoot for 5.5 in containers, especially if you're employing organic methods. This is because organic fertilizers are mineralized (broken down) more quickly at lower pH. Also, micronutrients (iron, copper, zince, etc.) are seldom a problem with organic (container) soils, as they are in mineral (native) soils.

[barryla61]

Originally Posted by fortyonenorth

The reason we manage pH is to maximize availability and minimize toxicities of nutrients. 6.5 is a "sweet spot" for in-ground growing, but I would shoot for 5.5 in containers, especially if you're employing organic methods. This is because organic fertilizers are mineralized (broken down) more quickly at lower pH. Also, micronutrients (iron, copper, zince, etc.) are seldom a problem with organic (container) soils, as they are in mineral (native) soils.

How would I lower the pH?

[artis]

What is you current pH in the container mix? What is the source and pH of the water?

If growing hydroponically, very, very, very dilute sulfuric acid is used to lower the pH of the water (adjust the pH of water, not the container mix!)

Organically, one could use collected rain water or high quality well water instead of municipal tap water to avoid issues with high pH. Pure and un-limed peat moss also has low pH (around 4). Usually, the commercial container mixes already have low pH (around 5.5), so pH is not a problem there at all.

[barryla61]

Originally Posted by artis

What is you current pH in the container mix? What is the source and pH of the water?

If growing hydroponically, very, very, very dilute sulfuric acid is used to lower the pH of the water (adjust the pH of water, not the container mix!)

Organically, one could use collected rain water or high quality well water instead of municipal tap water to avoid issues with high pH. Pure and un-limed peat moss also has low pH (around 4). Usually, the commercial container mixes already have low pH (around 5.5), so pH is not a problem there at all.

All containers are right at 7.0 pH
I water with natural spring water, we have a water line run directly from a spring on our farm