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“Animals that inhabit shallow waters have evolved to cope with variability in environmental conditions, but in the deep sea, there's very little change in oxygen or temperature or pH across the year,” Barry said.

It’s a good idea to test your soil — a survey of heavy metals, nutrients, minerals and pH levels costs less than $200 — and consider all the options for repairing it, soil scientists said.

Some plants, such as blueberries, azaleas and camellias, prefer acidic soils, i.e., soils with a pH below 7.

Once the pH levels get above 8, however, plant growth suffers because the roots can’t get the nutrients they need to survive.

In our tests, two yards had pH readings of 8.06 and 8.16; five others had alkalinity ranging from 7.70 to 7.98.