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A. Leaves of pecan and live oak trees are acceptable to use in gardens and as a mulch.

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I have been hearing misinformed people give reasons not to use pecan leaves. Most indicate these leaves put too much acid into the soil. This reason is WRONG. Jan 29, A. Pecan leaves contain tannic acid, and this fact has perhaps prompted rumors that the leaves will damage growing plants and should not be used as a mulch or in compost.

When this acid Estimated Reading Time: 1 min.

After chopping them, add them to mulch, add them to a compost pile or apply them directly to the soil surface.

Dec 23, But you can use the leaves to mulch beds. Experts say that when the tannic acid they contain reacts with alkaline soil, a neutral organic salt, calcium tannate, is formed. This is not shrubmulching.barted Reading Time: 40 secs. A: This is a gardening myth that should be put to rest. While needles and leaves from all trees may be acidic initially, they do no acidify the soil as they break down. Soil has a natural ability to buffer changes in pH. Soil acidity might increase slightly for a few weeks after leaves fall but the acidity will go away after a few months.

Oak tree leaves initially break down and become more alkaline.

However, the continued use of oak tree leaves makes soil become more acidic over time. Since oak leaves are somewhat large, chop them.