What to do about 5.5 pH soil?

I recently did some soil testing around the yard (it is a very fine sandy loam soil) and find that my unfertilized soil locations ae consistantly measuring 5.5 (using the color matching pH test). So now I am wondering if and what I should do to address this with my various fruit crops, I have a mix of Citrus, Figs, Peaches, Blueberries and Blackberries. From my research it seems that all the trees perform best with a pH of 6.0-6.5, with the exception of citrus where I find mixed information some saying 5.5 to 6.0. And of course we have the blueberries with their prefered 4.5 -5.5 pH range.

This year was a replanting year after loosing some fruit trees to age and freezes the last few years, so I have a mix of new and old citrus, peaches and blueberries. 2 or 3 of the old peaches will probably need to be removed in the next couple of years as they barely bloom anymore and the wood is splitting (I had to remove 1 last year and 1 this year, added 2 more to replace them), I want to stagger the ages of the replacements so they dont all die out at once.

Should I lime the whole thing (probably not practical it is a very big yard) , slow or fast acting, lime around the fruit trees only as the grass seems to be happy. As to the Blueberries, I have been feeding them organic table scraps (banana peels, coffee grounds, etc. along with a bit of decomposed pine compost topping) any change there? (I have 4 more blueberries on order that should be arriving any day, any suggestion on mixes for the planting hole?)

thanks Ike

For the blueberries using pine bark fines and peat in the mix would be good. If you can’t get good pine bark, just use some peat. Try to use rainwater, luckily you’re starting with a decent pH so a lot doesn’t have to be done. I would use an acid loving fertilizer though Holly-Tone, Dr Earth, or Cottonseed meal.For the trees no amendments. I would add compost and mulch every year, this will raise pH. I guess you could lime around the trees too.Except the Citrus. For figs 6.5 is good, but 5.5 is fine according to some university fig guides. I would do the same as for the stone fruit, compost, lime, mulch. The compost and mulch as they breakdown will increase pH.
For the blackberries I would amend soil with compost. All tolerate 5.5 but not ideal.
Your established trees are growing in the soil now, so I see no reason to add quick acting lime and take a chance of a burn. Slowly over time changing pH is better with slow acting lime, compost and mulch.
Mulch blueberries with any kind of pine bark. Monitor pH if needed to lower use sulfur, but be careful about using too much. Ammonium sulfate for a quick nitrogen fix works very well too, and lowers pH. 1 teaspoon per gallon. What I would do in your situation.

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Isaac, I think you’re fortunate. Given the choice between slightly acidic soil and alkaline soil, I’d rather have the acidic, which I do.

There may be something usable that changes the soil pH long term. If there is, I’ve never heard of it. Around here, soil test recommendations almost always come back suggesting the application of lime. It’s a temporary correction. Nature will eventually bring the native soil back toward its natural pH. Your local agricultural extension office can give you guidance on types of lime or gypsum and rate of application for your particular soil and crops if you choose to use those. They will be more familiar with your specific growing area than any of us.

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5.5 is usually fine for all fruit plants but it also has to do with other issues and bringing the pH up may be helpful for most plants besides the blueberries (and ornamentals like Rhododendrons) . You might consider a soil test through your cooperative extension to see the state of magnesium and other involved minerals before spreading lime. They will provide a specific, easy to follow recommendation to get your soil up to speed.

If you buy an inexpensive spreader, spreading pelletized lime is a snap and your lawn will be healthier even if it doesn’t affect your fruit plants much.

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I know the surrounding farm land is all magnesium deficient, so I suspect the yard is as well

Dolomitic limestone is the prescription for both issues.

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Go crazy w/ blueberries, chestnuts, chinkapins, pawpaws, rhodos, and mountain laurel.

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… and tomatoes galore.

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Strawberries like a low pH too. 5.8 to 6.2 is ideal. They will grow at 5.0.

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A good rule of thumb for most soils is that a ton of lime will raise the PH about 1 point. This calculates to about 45 pounds of ground limestone (about 1 bag) for 1000 square feet and is probably a good starting point.

Accurate application can be done with a drop spreader or spin spreader. You can spread ground limestone with a drop spreader, but not with a spin spreader. A spin spreader will spread pelleted lime or fertilizer but is about twice as expensive as a drop spreader. Pelleted lime is about 2X as expensive as ground limestone, but is more pleasant to handle. The finer the limestone, the faster is goes to work. Hydrated lime should not be used.

Keep the lime away for the Blueberry and any other acid loving plants! At the end of the season you could test the soil again of perhaps pay for a professional test and make adjustments next year. It may take multiple years to get the PH where you want it.

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That is about half the amount recommended by Cornell- for a sandy soil! I’m looking at a recommendation right now for a sandy soil with a 5.7 pH and for apples and they suggest 210 pounds of dolomitic limestone per 1,000 square feet. If it was clay the amount would be much more.

They are shooting for a pH of 7 for apples as they do aim high.

I have noticed that directions on bags of lime are much more conservative but I would run with Cornell on this and long have.

No need to go by rule of thumb- soil tests are a lot cheaper than the lime.

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Its easy to add more lime, but not so easy to correct problems caused by too much lime! If you submit a soil sample to NC State with a PH of 5.5 and indicate you want to grow apples or peaches, the recommendation they return is 1 ton acre. I know because that’s my exact situation on the farm where I live.

Looks like Cornell’s estimate would be closer to 4 ton’s/acre.

I can not explain the difference between these two very different recommendations.

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I don’t doubt that is true for your region, but the rate may vary depending on the soil composition. For instance, soil from the Coastal Plain and Piedmont areas both tend to be acidic; however, the first is sand based and the second, clay. Since the soil types have different properties, recommendations for irrigation and amendments are likely to vary, which is the reason that submitting a soil sample through the local cooperative extension is a more reliable way of determining how best to correct pH problems than just following the well intended recommendations from those of us who don’t have an actual analysis of his land.

If it helps the area soil survey map shows the local soil type / types as Official Series Description - BEAUREGARD Series and Official Series Description - BLEVINS Series With the dividing line basically going through the house.

Muddy makes a good point about how soil types change from area to area and how these different soil types impact the requirements for lime, fertilizer or water. My 1 ton/acre suggestion does not take soil type or structure into consideration - its just a general rule of thumb to get started.

It takes surface applied lime a long time to work its way down into the root zone, so it will take multiple years for the lime to provide the full benefit. In the prefect world the lime would be plowed into the soil several months before the trees are planted.

I did not plow down the lime like I should have before I planted my trees. Its taking multiple applications over multiple years to get the PH of the soil at 6 inches deep into the 6.5 area.

If I had a chance to start over again I would plow the lime in and retest. Order my trees several years in advance to make sure I got the variety/rootstocks I wanted and cover crop the land heavy to improve the tilth and control the weeds. Then plant the trees.

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It is strange that they make that rec without adjusting to soil texture. Anyway, have you followed their instructions and gotten as much a boost as they suggest? I’ve never had the pH go to high from following Cornell.

I’m in a similar situation with the high ph, sandy soil, and trees in the ground. What effect do you think coring might have on shaving some of those years off since plowing/tilling is undesirable?

I’m sure they adjust for CEC and organic matter

I had a low PH that I was trying to raise. Did I understand have high PH you are trying to lower?

Texture is even more influential that either of these two, although they are related.