If you're using an organic acid like vinegar or citric acid, you might have some issues with bacterial growth (especially if you're also premixing fertilizer). I'd imagine that it will depend to some degree on the temperature of the water and the amount of time that passes before it's used.

I won't be adding fertilizer to it. Maybe use battery acid instead of vinegar? Growth shouldn't be a problem if the barrel doesn't let any light through (like regular rain barrels)

They have fertigation systems to mix solutions(vinegar,fertilizer,etc) with water at the proper ratio. Look it up.

Battery acid, are you joking me? You would kill your plant, soil, and damn near anything it touches. Don't use battery acid, it's extremely caustic!

Healthy soil, given plenty organic matter should buffer pH to some degree. I seen blueberries growing right next to vegetables, thriving. So make sure you take care of your soil, add a inch or two of compost and mulch(leaves,straw,etc) annually.

Some blueberry growers use sulfuric acid, which is in batteries, to lower pH. I would not mess with it at home, it will eat right through you.

Most use sulfur to lower pH. Though, i did hear Dr.Ignham talk down on it, saying it's a fungicide..

Here's a discussion on it.

Here is a link that might be useful: Battery acid, blueberries?

NN, when someone says, 'battery acid,' they mean sulfuric acid. It works well to reduce the pH of large quantities of water. While it is a strong acid, with proper precautions, it is reasonably safe and easy to use. The stuff from the auto store is only about 40% sulfuric acid. Wear some goggles, some acid resistant gloves, and always remember to add acid to water.

Boy, that thread is full of pearlclutchers that have obviously never had a chemistry class.

This post was edited by nil13 on Mon, Mar 3, 14 at 20:48