Are Mycorrhizal Inoculants Worth It When Planting Trees?

Native Fungi Usually Suffice

Mycorrhizae are beneficial root‑associated fungi that trade nutrients for plant sugars. In soils with decent organic matter, they’re already present. Adding commercial inoculants rarely boosts tree establishment.

When They Might Help

• Very poor soils: pure sand, heavy subsoil clay, or sterile fill.
• Container‑grown trees planted into harsh sites.

For most landscape plantings, focus on loosening a wide planting area and incorporating compost—that stimulates native mycorrhizae naturally.