How to Grow and Care for Rockrose

Originating from the coastal regions of the Mediterranean, rockrose (Cistus) is a genus of flowering, fast-growing evergreen shrubs that is characterized by dense green foliage; delicate, papery flowers; and aromatic leaves. Among the most ornamental of all Mediterranean flowers, rockrose are hardy shrubs that are drought-tolerant, deer-resistant, and can withstand extreme heat. They grow well in poor quality soils and often survive in locations where other plants can’t. They make great additions to rock gardens, exposed garden beds, coastal areas, and dry banks alike.

Rockrose is best planted in the early spring.

Rockrose Care

Depending on the variety, rockrose may grow in a spreading, groundcover habit, or in large mounds reaching several feet high. Rockrose is able to withstand severe heat, strong winds, drought, and salt spray, making it an effortless addition to most North American gardens. The plants are commonly used in informal hedgerows, as ground cover plants, or for erosion control.

In the early spring and summer, each flower only blooms for a couple of hours before dropping and making way for the next group of flowers. This short bloom is a distinctive characteristic of the rockrose genus.

Light

Plant rockrose shrubs in a location that receives full sun for several hours a day. They will not survive in shady locations.

Soil

Rockrose plants grow well in poor-quality rocky soils as long as they are well-draining. Choose a spot with deep soil so that the rockrose can establish deep and spreading roots. Rocky and sandy environments are fine for rockrose plants. Its preferred pH range is between 5.6 and 7.5.

Water

Generally, rockrose are drought-tolerant plants that do not require watering outside of regular rainfall. However, during the first growing season rockrose plants should be watered weekly to help them mature and establish healthy roots. When watering your rockrose be sure to provide a deep, thorough watering that drenches the entire root ball to encourage strong growth

Temperature and Humidity

While rockrose can tolerate heat and high temperatures but they do not do well in cold climates and cannot survive heavy frost. The plant can survive in moderately humid conditions but does not like tropical humidity.

Fertilizer

Rockrose plants do not require regular fertilizing, except during the first growing season to help them get established. Fertilize once in the early spring with general-purpose, slow-release fertilizer to kick start growth. After they are established normally do not need fertilizing.

Types of Rockrose

There are approximately 20 species in the rockrose (Cistus) genus as well as a large number of hybrids. The following are some of the most popular varieties:

• Orchid rockrose (Cistus x purpureus), 2 to 4 feet tall and wide with pink flowers
• White rockrose (Cistus x corbariensis), 2 to 5 feet tall and wide
• Pink rockrose (Cistus creticus), 3 feet tall and white
• Common gum rockrose (Cistus ladanifer), 3 to 5 feet tall with white flowers
• Magenta rockrose (Cistus x pulverulentus 'Sunset'), 2 to 3 feet tall and 6 to 8 feet wide

Pruning

Rockrose plants have a dense, bushy growth habit and require occasional pruning in order to keep them compact and healthy. They cannot tolerate heavy pruning so maintenance should be kept to a minimum where possible. Rockrose plants should be lightly pruned after they have finished flowering to help preserve the buds for next year’s bloom. In the spring they may need pruning to help remove winter damage and correct the shape but this should be done conservatively. Branches on a rockrose plant should never be pruned below the last leaf as they will be unlikely to recover.

Propagating

Cistus can be propagated from softwood cuttings:

1. In the late spring or early summer, select young, healthy, non-flowering shoots about 6 inches long.
2. Fill a 4-inch pot with potting mix and poke a hole in the center. Dip the cut end of the shoot in rooting hormone in bury it in the potting mix.
3. Place the pot in a warm location with good air flow and out of direct sunlight. Bottom heat is ideal to speed up the rooting process. Keep the soil evenly moist. The cuttings root in about one month.
4. Let the new plants grow for a few weeks before transplanting them in garden soil or larger containers.

How to Grow Rockrose From Seeds

Rockrose seeds are not commonly available and using the seeds of a hybrid won't result in a plant that is true to the parent. Therefore propagation from seeds is not recommended.

Potting and Repotting

Rockrose plants can be grown in containers as well as in gardens. Because they prefer dry conditions, they generally don’t do well when planted in small containers that require frequent watering. Instead, choose a larger container so that the soil can stay more evenly moist and the plant can be watered less often. Rockrose plants do well when transplanted from containers to the garden as long as there is minimal root disruption.

Overwintering

Rockrose should be planted in a location that is protected from cold winds and heavy frost as these conditions can damage the plant, impacting the following growing season. Moderately cold, dry, and short winters are ideal for rockrose plants as it the Mediterranean winters they are accustomed to.

If your climate is too cold to grow rockrose year-round outdoors, you can grow it in a container and bring it inside in October. Keep it in a bright cool place and water is sparingly, just enough so the soil does not dry out.

Common Pests & Plant Diseases

Generally rock rose does not have serious pests and diseases. Aphids like to feed on rock roses. The leaves can be covered with powdery mildew but those don't jeopardize the survival of the plant.

How to Get Rockrose to Bloom

Failure to bloom is usually due to lack of sunlight, or excess nitrogen, which will make the plant grow abundant foliages but no flowers. Feed the plant with a bloom-boosting fertilizer that is high in phosphorus.

Common Problems with Rockrose

Rockrose is a plant with relatively few issues. One thing to avoid is poor water management, especially too much water or irrigation, often caused by soil with inadequate drainage, which can lead to root rot. Rockrose plants do best in dry conditions but should not be overwatered.