Harvest a healthy Tribulus plant for herbal use when the plants begin to blossom. Look for a mature plant that displays even growth and color throughout the entire plant. Cut off the outer portions of the stems that contain young leaves and flower buds that are almost ready to open.
Place the cut Tribulus vegetation in a colander and rinse well under a gentle stream of cool water. Dab the stems with a paper towel to absorb excess moisture. Gather the ends of the stems in a bunch and tie them together with a piece of string. Hold the stems upside down and lower them into a paper bag. Tie another piece of string around the top of the bag and the stems to keep the Tribulus clean and free from dust and bugs while it dries. Hang the bag containing the stems in a dry area out of direct sunlight.
Check the Tribulus every few days. Remove the vegetation from the bag when it feels dry and brittle. Strip the leaves off the stems.
Place the dried leaves in a pestle. Crush the herb into a fine powder by grinding the brittle leaves against the bottom and edges of the pestle with the mortar. Store the powdered Tribulus in a clean, dark jar.
Add up to 1 teaspoon of the powdered Tribulus to a cup of hot water to make tea. Stir well. Consume the tea in the morning and early in the evening.