Bark and pH

by Tristan Gooley

Each tree's bark will have its own pH, and some are more acidic than others.

Larches and Pines are notoriously acidic; Birch, Hawthorne and Oak are acidic too, but slightly less so.

Rowan, Alder, Beech, Linden, and Ash are little less acidic again, and Willow, Holly and Elm are getting closer to neutral. Sycamore, Walnut, and Elder are alkaline.

The less acidic the bark is, the more growth you are likely to see from colonizing plants and lichens.

Pine bark is often bare, whereas Sycamore might have a glorious guest hanging off its bark.
— Tristan Gooley, New York Times Bestselling author, The Lost Art of Reading Nature Signs, Bark

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Bark and pH


  1. Bharat Shahane on June 18, 2023 at 12:16 am

    Greetings from India!
    Any idea – Is rotten oak bark and dried/crushed oak leaves a good potting medium for cattleya orchids and begonias? Thank you!

    • The Daily Gardener on October 4, 2023 at 8:18 pm

      Hi Bharat –
      I’m no orchid expert but I can tell you that I use bark, perlite, & a little moss for my orchid medium.

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