Calcareous Soil Concerns

We’re looking at a property that we really like. Soil survey says it’s calcareous throughout and ~40 inches deep to weathered shale. There are chalky chunks around (0.5-2 inches), especially towards the tops of the hills. It was apparently once an almond orchard, but now it’s just seasonal grasses with a few scrubby bushes. Almond trees persist on some nearby hillsides and creek bottoms. I also have the neighbors drilling report (below) that makes me think rooting depth won’t be a problem(?). I will test the soil, but I don’t expect any big surprises.

Is there anything we should worry about? Our biggest interests are apples and pears, which shouldn’t mind chalky soil, right? Stonefruit would be a distant second priority, and blueberries will definitely require accommodation. Any rootstock ideas/suggestions/warnings would be awesome.


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Is this for a commercial venture or just a few hobby trees for the family? Either way the soil chemistry analysis will really be required as a starting point.

A commercial venture but not a livelihood, nobody will be financially reliant on farm income. At most 20 acres of mostly apples. I’m getting the soil checked, but wanted to ask if there are any glaring red flags I’m somehow missing. Performance on chalky soil doesn’t seem to get a lot of attention, and I think there’s plenty of chalk around, as far as I know it’s not a big problem by itself.

That is some deep ground…If We dug 500 ft down, it would be 490 feet under water. I can strike the water table at around 10 ft where I live. I start striking mud at around 5 ft down

My suspicion is that the test results will show that the soil is too alkaline for a productive apple orchard. It is easy enough to walk the lot and do some quick field tests for confirmation.

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What would be generally reasonable limits for a productive apple orchard?

And yes, pretty deep wells.

Your cooperative extension can either do a test for you or direct you to a reliable lab that will let you know what amendments your soil needs for commercial apple production. The cost is under $20 for the basic test. They often perform pH tests for free.

Apples do best in a slightly acidic soils and usually do fine in soils between about 5.8 and 7.5. It is easier to treat acid soil than alkaline.

Apples will grow in Calcareous soil, but I am not sure what root stock is optimal.

Yeah, I see anecdotal reports of good apples from calcareous soil, but can’t find much information about rootstock choices.

This is putting the cart before the horse since we don’t have a soil analysis yet but Calcareous soils (pH > 7.5) render iron and zinc nutrients unavailable for tree uptake.

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