What concerns should I have about the wider ecosystem if I’m considering adding Mycorrhizae to the soil around my roses?
Question:
What concerns should I have about the wider ecosystem if I’m considering adding Mycorrhizae to the soil around my roses?
Answer:
As you probably know, based on your question, mycorrhizae are soil-based fungal organisms that form symbiotic relationships with almost all terrestrial plant roots, exchanging their vastly greater surface area’s ability to absorb and transfer water and nutrients from the soil for the plant’s photosynthetically produced sugars–both fungus and plant benefit from this beneficial partnership. Unsurprisingly, there are a number of products marketed to home gardeners to boost mycorrhizae populations in their soil, governed by the logic that adding these organisms will boost plant growth, as well.
While there aren’t any huge ecological concerns to adding these products (after all, it’s a naturally occurring life form that is present wherever plants are found), it’s unclear whether adding them actually produces positive effects. If an environment is amenable to plant life, mycorrhizae are already present and generally thriving at close to optimal levels, and boosting their population hasn’t been demonstrated in peer-reviewed studies to have a correspondingly positive impact on the plants. I suppose it’s possible that adding them to something like a sterilized plot could help theoretically, but they require for their survival the same rich, organic matter that plants do, so they probably wouldn’t do well in that situation, anyway. You can read more about the topic in these links:
Univ of CA Division of Agriculture and Natural Resources page on Mycorrhizal inoculants
The Garden Professors blog entry on mycorrhizae
In short, I don’t think you have to worry about any ecological impact as long as you are using the product as directed (and not, for example, dumping huge amounts in your garden), but you may be wasting your garden budget for little to no return from your plants.