Parsley is a leafy culinary herb native to the Mediterranean that grows well in the home herb garden. Growing parsley successfully in the herb garden requires a sunny spot, nutritiously rich soil and consistent soil moisture. Parsley is a biannual in frost-free climates. It is a member of the carrot family and identified under the species name Petroselinum crispum.
One of the best tips for growing parsley successfully is choosing a sunny spot. The term "full sun" means at least six hours of direct sunlight each day. Parsley thrives with six to eight hours of sun a day. It is tolerant of partial sun, four to six hours a day, or partial shade, two to four hours a day, but may not grow as vigorously or be as flavorful.
Parsley grows best in deep soil rich in nutrients and organic matter. To improve nutritiously poor soil or structurally poor soil, a 2- to 4-inch (about 5- to 10-cm) layer of compost can be spread over the garden bed and dug into the top 8 inches (about 20 cm) of soil before planting. A soil pH of 6 to 7 typically is ideal for growing parsley.
The best time to plant parsley is in the spring after the last frost date. Parsley can be planted from seed or from starts either raised indoors or purchased. The plants should be spaced 10 to 12 inches (about 25 to 30 cm) apart and planted at the same depth in the soil as the plants were in the nursery pots.
Consistent moisture around the roots is important for parsley. The plants should be watered twice a week, or when the top 1/2 inch (about 1 cm) of soil starts to dry out. A layer of mulch, 2 to 4 inches (about 5 to 10 cm) deep, can help keep moisture in the soil and regulate soil temperature. The mulch layer should be spread when the seedlings grow 6 inches (about 15 cm) tall. Shredded leaves, grass clippings and well-rotted compost make good mulch for parsley plants.
Parsley seeds should be planted to 1/8 of an inch (about 3 mm) deep, typically in the spring right after the last frost date. Soaking the seeds for 24 hours before planting can help shorten germination time, but it usually takes about two to five weeks. When growing parsley from seed, the seedlings should be thinned to a spacing of 3 inches (about 7 cm) apart at 2 to 3 (about 5 to 7 cm) tall.