Roman Chamomile (Chamaemelum nobile) is a creeping, low-growing perennial valued for its fragrant, apple-scented foliage and daisy-like flowers. Unlike German Chamomile (Matricaria recutita), the Roman variety is a hardy perennial that forms a dense mat, making it suitable as an aromatic groundcover or a lawn substitute. Its small white and yellow flower heads are harvested for herbal tea (which can be slightly bitter) and are frequently distilled for their high-ester essential oil. The plant is winter-hardy in USDA Zones 4-9 and tolerates light foot traffic once fully established.
Establishing the Planting Site
Selecting the proper site for Roman Chamomile involves balancing light and drainage. Full sunlight encourages the most prolific flowering, but the plant tolerates partial shade, which is beneficial in regions with intense summer heat. The ideal soil should be well-draining, preferably a sandy loam, to prevent roots from sitting in excess moisture.
Soil pH should be slightly acidic to neutral (5.6 to 7.5). If starting from seed, sow them shallowly in early spring or fall, as the tiny seeds require light to germinate. For quicker establishment, space transplants or cuttings 8 to 12 inches apart to allow runners to spread and create a solid groundcover mat. Transplants require consistent moisture until the root system is established.
Routine Care and Maintenance
Once Roman Chamomile has settled into its location, its maintenance needs are minimal, reflecting its drought-tolerant nature. Overwatering is a significant threat to established plants, as persistently wet soil often leads to root rot in the dense, creeping mat. Watering should be deep but infrequent, allowing the top inch or two of soil to dry out completely between applications.
The plant thrives in lean soil, and fertilization is discouraged because it promotes weak vegetative growth at the expense of flower production. If the soil is extremely poor, a single, light application of a high-phosphorus blend in the spring may encourage better blooming. Weeding is most important when the plants are young, as their spreading habit struggles to compete against vigorous weeds. Once the chamomile forms a dense cover, it helps suppress most competing weeds.
Good air circulation prevents common fungal issues like powdery mildew, which can develop in humid conditions or with overhead watering. Pests such as aphids can occasionally appear, managed by spraying affected areas with a strong stream of water or applying insecticidal soap. The plant’s overall resilience and low nutrient requirements make it a relatively self-sufficient herb once mature.
When and How to Harvest
Harvesting Roman Chamomile flowers should begin in early summer when the blooms are fully open and the small white ray petals are flat or slightly reflexed. The best time to pick the flowers is on a dry morning, after the dew has evaporated but before the intense heat of the day, when the essential oil content is thought to be at its peak. Only the flower heads themselves should be harvested, as the stems contain minimal beneficial compounds and can introduce bitterness to teas.
To harvest, gently pinch or snip the flower head just below the bloom. The flowers should be dried immediately after picking to preserve their aroma and medicinal qualities. Spread the fresh flowers in a single layer on a screen or tray in a warm, dry, and well-ventilated location away from direct sunlight until they are completely crisp, usually about two weeks. Once dried, store the flowers in an airtight container in a cool, dark place, where they maintain potency for up to a year.
As a perennial, the plant benefits from post-harvest management to maintain its dense form and encourage new growth. A light shearing or mowing of the spent flowers after the main bloom period will tidy the plant and prompt it to spread more vigorously via its runners. While the plant will naturally spread, installing a six-inch deep edging can help contain its growth if you are concerned about it moving beyond its designated area.