For people who love to garden as well as people who garden as part of their business, learning the best ways to inspire healthy plant growth is essential. One of the best plant nutrients is a mycorrhizal fertilizer. This is a fertilizer that is composed of mycorrhizal spores. These nutrient-dense spores come from the mushroom family of fungi and offer a continual base of nutrients to plants. This ensures the soil does not run out of a healthy food source for their plants.