Growstone pH rise

[Ray]

Originally Posted by missbehavecutie

Anyways;
i have been doing some research on this and i wouldn't recommend using lemon juice or vinnegar i would us a sprinking of baking soda instead , using lemon juice to regulate the substrate ph will alter the mineral composition which could impede your fertilizer from being absorbed by orchid roots, because certain compositions change the ability of the orchid to absorb nutrients.

Sorry Leah. I'm not picking on you (although it may seem that way), but this is simply bad info that shouldn't be shared, as-is, so I am taking the opportunity to correct the facts.

► Adding an acidic compound like lemon juice or vinegar - in the concentrations that won't kill the plant - isn't going to change the mineral composition of anything.

► Baking soda is going to affect the pH just as much, if not more, but will cause it to increase, not decrease - just the opposite of what you're trying to accomplish with grow-stones.

► I don't know this for certain, as I've never done so, but I'd bet baking soda sprinkled on potting media can kill roots to which it makes contact. That certainly would inhibit the plants' ability to absorb anything!

► Changes in pH within the pot only affect the orchids' ability to take up nutrients if it makes them insoluble. If you're referring to the classic "pH versus nutrient availability" graph, read this.