No not 10-10-10 that's probably mostly nitrate nitrogen. It will say on the bag percent of nitrogen in nitrate form and percent in ammonium form. If it doesn't say don't use it.

Use 21-0-0 ammonium sulfate if your pH is 5 or higher. Use urea if below 4.5.

There are also special fertilizers for acid loving plants. Use one of those according to directions.

Well, what is nitrate nitrogen and why is it bad? Sorry for the ignorant questions, i'm new at this and just trying to learn....thanks...

Nitrate is only bad in larger amounts than blueberry can convert to a useable form. In acid soil most of the nitrogen isn't converted from ammonia to nitrate. So blueberries have evolved to use primarily the ammonia form of nitrogen.

Nitrates are ammonia, NH4, that has been oxidized to the nitrate form, NO3, by soil bacteria.

Someone feel free to edit my chemistry if necessary. But basically it's just two forms of nitrogen, N, present in the soil.

This post was edited by fruitnut on Mon, Apr 28, 14 at 20:36

Just wanted to add to fruitnut's post.

Nitrate fertilizers have a net effect of raising the soil pH, because as the plants absorb nitrate ions, they exude hydroxyl (OH-) ions into the soil solution.

Ammonium fertilizers on the other hand have an acidifying effect because when ammonium is oxidized to nitrate, H+ ions are released.

And yes, the blueberry family has adapted to using ammonium, although nitrate in itself is not toxic. For most other plants, however, excess ammonium is more toxic than excess nitrate.

Confusing enough? :)

Basically, there are 3 possiblities:

1. Calcium, sodium or potassium nitrate: after the nitrate has been absorbed, the hydroxides of these metals remain, increasing soil pH.

2. Ammonium sulfate or phosphate: after bacterial action, nitric acid and sulfuric or phosphoric acid (respectively) remain. Same goes for urea, which gets converted into ammonia, then ammonium, and finally nitric acid. So your best acidifying fertilizers are ammonium sulfate, urea, diammonium phosphate and monoammonium phosphate.

In containers, the absence of nitrifying bacteria will blunt the acidifying potential of these fertilizers, but they will still acidify to some extent.

3. Ammonium nitrate: neutral effect on soil pH because they "cancel out".

This post was edited by Slimy_Okra on Mon, Apr 28, 14 at 20:49

And to add a little bit more to fruit nut and slimy, blueberry plants do not produce much of the reductase enzyme to break down nitrate forms of nitrogen into usable nitrogen. It can end up accumulating in the plant tissue to toxic levels.

Edit: phone typing is not ideal

This post was edited by charina on Mon, Apr 28, 14 at 22:00

You can do as fruit nut said, ammonium sulfate or urea depending on ph. You can also use a general purpose fertilizer for acid loving plants like miracle grow if you wish.

RM

You can buy Ammonium Sulfate on Amazon, one of the cheapest fertilizers around. If you don't like buying online, Miracle Grows makes a product Mir-acid or something like that. If your too cool to use soluble, you can use the organic Holly-Tone or cottonseed meal.

I have been using cottonsead meal for several years with good results, its a slow release organic alternative. Its also pretty cheap, I picked up a 40lb bag for around $22 at local feed and seed store