There are several ways to use cinnamon for plants:

1. Sprinkle cinnamon in the soil: You can sprinkle cinnamon in the ground before planting to prevent the onset of diseases. Sprinkle a thin layer of cinnamon over the soil and mix well before planting.
2. Apply cinnamon to the roots: Cinnamon can also be applied directly to the roots of plants to improve their growth and health. Sprinkle a small amount of cinnamon on the roots before planting or mix a small amount of cinnamon into the water before watering the plants.
3. Sprinkle cinnamon solution on leaves and stems: Mix a small amount of cinnamon in water and spray the solution on plant leaves and stems to help prevent disease and improve plant health. You can also mix a small amount of cinnamon in a little oil and apply it to the leaves and stems to protect the plants from insects and pests.

It is important to remember that although cinnamon is a natural and safe choice for plants, it should be used sparingly. Too much cinnamon can be harmful to plants and can cause excess nutrients. As always, it’s important to do a test on a small section of the plant before applying cinnamon to the entire plant to make sure it doesn’t cause damage.