Choose a sunny garden location with moderately rich, well-drained soil. Parsley grows best with six to eight hours of sunlight. If the soil is heavy or low in organic matter, amend the area with 2 to 3 inches of aged compost.
Soak the seeds in water for 24 hours before planting. Start the seeds indoors six weeks before the last frost date, planting each seed 1/8 inch deep. Keep the soil evenly moist and be patient, as parsley may take nearly a month to germinate.
Thin the seedlings to 8 inches apart once they reach 3 inches in height. Transplant the young plants into the garden once the danger of a late frost passes. The seedlings are often thin and easily overlooked -- mark the planting site.
Mulch the seedlings well to prevent dehydration and keep the soil moist until the parsley establishes. Unlike sage oregano and other drought-tolerant herbs, parsley does not tolerate dry conditions. Water established plants deeply once each week.
Fertilize parsley with a balanced garden fertilizer (5-10-5) once during the season. This herb is usually ready to harvest two and a half to three months after planting.