A compromise might be to prune the oak tree. To get more light to your berries, you can limb up the lower branches and thin out the upper branches. I think that cutting down a tree should always be avoided if at all possible. One benefit of the tree is that its fall leaves will provide an excellent mulch for your bushes every fall. You can pile up the leaves between the bushes to prevent weeds. Before you apply each season's new batch of leaves, you can rake the decomposed leaf mold up near your bushes from the rows between them. You can then pile up all the all the great leaves in the middle. It will save you the cost of buying mulch or hauling it from further away. You might get some competition for water and nutrients between the trees roots and your bushes, but blueberries have very shallow roots that might not be hurt as bad as some other plants. You may find that the plants nearest the tree will need a bit more water and fertilizer.

I haven't used Hollytone but many people do successfully. It's a lot safer than ammonium sulfate. The later is safe if dissolved first at a modest concentration. I got my fastest growth in pots by mixing 1 teaspoon per 2.5 gallons and applying once a week. In ground once a month should do. Small frequent doses are much safer than one large shot. Right now I'm mixing 1 ml per gallon which is, I think, a fair amount less than rate above. Where I've burned plants with ammonium sulfate is applying it dry at excessive rates and watering in. That can fry the roots. PS: A teaspoon is 5 ml. So rates above are 2 ml per gallon vs 1 ml per gallon. This post was edited by fruitnut on Wed, Jul 30, 14 at 12:00

"I don't understand how evergreen can acidify soil if they never drop their leaves. Those needles stay on the tree year round so how do they amend soil exactly?" They don't as such (see below, however...), but...trees do remove the resources from the soil around them, so it's not exactly true to say that plants and plant parts don't influence the soil pH or soil resources (same thing, really), around them. Evergreens are famous for drizzling dying needles in piles below them, although it depends on the evergreen (less than one might imagine, I've seen few that didn't, really, that were needle-based). Yes, we can argue for days about "needles" and the definition thereof, but they do age and are replaced. The full explanation follows. As they compost in place, they rot and generally get pretty close to neutral pH (most sources say 6-8. That seems about right from casual measurement). That compost has a lot of free binding points for resources (you can look into CEC--cation exchange capacity--if you want). Those can't just stay empty, it's a matter of energy potential. So they'll grab onto a hydrogen ion from water, letting the oxygen go back into the air. Hydrogen ions are weak acids. The overall result is a weakly acid pile once all is said and done and it's gone from compost to indistinguishable from dirt. How acid depends on the CEC, which depends on the initial composition and the admix into soils. This is not simple. But if you isolated it back out and measured it, let's just estimate it at pH 5.5-6, but a volume low enough that it's not having too terribly much impact on the soil overall. That's easy to fix with a little calcium, or whatever a soil test recommends. The hydrogen only weakly bonds. The calcium has a dual, and much stronger, bond. Any plant pulls calcium (in larger amounts), magnesium (smaller), and potassium (in the middle) from the soil, reducing pH. A soil test would be required to tell you how much, but it does tend to drift faster within a tree's root system than otherwise. Succession comes into play with other plants like dandelions, which don't mind absolutely awful soils. So the situation isn't simple here, as those will throw deep tap roots and mine resources from deeper in the soil, bring them up, and overall richen the topsoil beyond what it had previously. Deeper tree roots can do exactly the same thing. But those resources end up bound into the tree's wood, leaves (needles, in this case), and roots. Tapped from the soil, however, leaves space only for hydrogen again, as described above, or for something else entering soil solution from the solids (aluminum, a strong acid and also toxic, is another possibility, but you could get calcium if you have undissolved calcium carbonate in the soil too). As it relates to blueberries and cedar trees, the rough answer is, "probably not." Cedars like a 5.5 to 7.2 pH (depending on the species, I didn't track back that far as the sub-question didn't really apply). Mine do very well at 6.2, Thuja standishii x plicata. Blueberries would prefer 4.5 to 5.5, so there isn't much overlap there. Trying to grow them too closely together is not going to end well, creates a gradient in the soil that's awfully sharp, and one would be playing games with sulfates and calcium that I really don't want to think about. And, as always, mind the sulfur at the surface; it tends to turn to sulfur dioxide and nobody needs the atmospheric smog and greenhouse gasses. Dig it in, but mind the root systems and patches of extremely low pH.

Thanks Karin for the heads up that we were given the right information...to keep the rocks away from the plants base. And hanging head on the sand cherry we most likely killed...It was fairly large...my husband got a decent size root ball but I felt he could have taken more. We did NOT trim the plant back so the volume of the top matched the volume of the roots. Once moved I've given it miracle grow and watered deep...But again we had it smothered with rocks up high on it's main base. Would it pay to trim the shrub shorter to after planted to help counter that we hadn't done it before transplanting? Thanks on the kind words of the waterfall...I was really trying to go with the "natural" look...then that weeping maple suckered me into purchasing it. We vacation around waterfall trails and have for years. So when I suggested a water fountain feature in the backyard...my son who was 11yrs. old at the time commented he felt that a waterfall would be more appropriate. And that is how it all started. I originally wanted a horseshoe of rocks placed so that a larger rock/bolder could sit a top. And have the bolder drilled and water come down over it. Which sort of reminded me of a smaller version waterfall called "Ash Cave" down in Hocking Hills area of Ohio. But the kit we purchased was HUGE...and the man working the bobcat and my husband felt we were going to be wasting so much materials by making as such...and it went from there. I do love it and the sound it makes. It's built into a hill so I really don't have a "HUGE" pile of rocks coming up unnaturally from the ground to form it. Our neighbors who walk by complain because you can't really see it from the road...but only hear it. But to make it any other way would of made it look more unnatural. On the corner from us the previous owners made a rock garden of large rocks...so what rocks you do see from our backyard when not viewing the waterfall...looks natural to the area I think because of what the previous neighbors did. One neighbor came by and visited...and teased that HGTV called and wants their waterfall back. lol We also have a porch swing back there along with a few chairs on the back patio. And off the other patio where we have a picnic table you can view the waterfall as well. So it's ideally placed for our own enjoyment... No one can get over the size rocks used to make this waterfall. I think that alone helps make it look more natural than using just smaller ones that one can lift with their hands. Big project took most of the summer. But well worth it.