The premise is that citrus and blueberry both are acid loving plants. While I have commonly heard citrus are acid lovers, I can't find any 'concrete' information supporting this.

The sources I have read such as university papers suggests citrus do fine in moderately acid to very gently alkaline soils.

I am using Foliage Pro for my 3 citrus trees. When I got them in the cool of spring they all had leaves showing nutrient deficiencies of one sort or another. Today the leaves are all perfect looking. I am certain the warmth of summer had a lot to do with that, but the foliage pro didn't hurt either.

Thanks JAG. Switching gears then, what soluble fertilizer do you use on blueberries?

I don't ;) I used to grow blueberries in containers, but had a heck of a time overwintering them so moved them all into the ground. You should be fine with MG plus some gypsum(in the mix) and epsom salt in the fert solution. Others may have different approaches. I would also recommend a little vinegar in the irrigation water as most water sources are fairly alkaline (a tablespoon or two per gallon should be enough in most cases)

Got it, thanks!

So, I'm a newbie here and trying to figure all this out.
I guess the reason you don't want to use Foliage Pro acid loving plants is because it will sweeten the soil. But... you can counter act that by adding adding some vinegar, right?

What if I have an acid loving salt hating plant? Will vinegar be bad for it? How would you fertilize a plant like that?
Thanks!

In a container there really is no such thing as a salt hating plant. The overall salt accumulation (fertilizer=salt) is either too high or it isn't.

It occurs to me my above response is about as clear as mud.

What I mean is that in a ground soil salts can and do accumulate and some soils are naturally 'salty' therefore some plants won't do well in those soils.

In a container using a suitable potting mix the accumulation of salts is handled by watering. Watering so that some water exits the drainage hole each time flushes salts from the mix reducing the odds of salt accumulation becoming toxic to any plant to virtually nill.

Of course I am not suggesting that mixing a fertilizer at 10x normal strength is a good idea either. The moral is that 'salt sensitive' plants generally won't encounter the same issues in a container with a suitable growing media and reasonable watering/fertilizing program as a ground soil already at the upper limits in terms of salt content for a given plant.

Thanks for the clarification justaguy. That helps!
So, am correct in my thinking that I can use foliage pro on an acid loving plant if I add a tablespoon of vinegar per gallon?
Should I use vinegar at the same time as the fertilizer (in the same water), or is that too much for the plant at once? Only use it at other waterings?

Thanks for any advice.
-Piri

You can use vinegar whenever you water, but there really ought to be a reason for your doing so. Counteracting alkaline water would be one reason (breaking down the buffers), liberating nutrients not otherwise being liberated would be a reason, but adding vinegar will not change the source of nitrogen in a fertilizer. Urea remains urea, nitrate remains nitrate, ammonia remains ammonia etc.

In other words if you want a source of nitrogen that tends to acidify, choose that. If you don't want a source of N that acidifies, choose one that doesn't.

Vinegar isn't going to change the chemical properties of the N source.

My personal *opinion* based upon my *personal* experience is that Foliage Pro is just fine for acid loving plants. I asked about this on another forum earlier this year when I started with citrus trees. I was told by some that a fertilizer for acid loving plants had to be used and just could not wrap my brain around why. So I just used FP. All signs of nutrient issues that were present when my trees arrived cleared.

While I have much to learn in terms of the science behind things, it is clear from what my eyes tell me that it is not necessary to use an 'acid fertilizer' just because a plant does best at an acidic pH.

The chemical properties of the fertilizer are just one part of the puzzle. The growing media and water source, anything around the plant's roots needs to be considered as a part of the equation. If one doesn't wish to stress over the details I would say 'just do it' (whatever 'it' is) and let your eyes tell you if it is working to your satisfaction or not.

In a container we can alter the environment around our plant's roots to respond to how the above ground portion is doing much faster than we can with in ground plants so why not have some fun, take it easy and experiment a bit?

If the plants don't like it, they will let us know :)

ok, thanks!