Answer: To be honest, it's best to plant junipers in native soil, unless you can amend the entire growing area and not just the planting holes. The reasoning behind this is that if you amend the soil in the planting holes only, the roots will tend to remain in the general vicinity where the soil is rich rather than exploring out into the native soil. This can eventually girdle the plant and it will die, and it will also make them more prone to blowing over in high winds because of a stunted root system. So, if you can amend an entire bed with organic matter prior to planting, do so. Otherwise, just use native soil.
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