How to Grow and Care for Rockrose

Rockrose (Cistus) is a genus of flowering, fast-growing evergreen shrubs characterized by dense green foliage, delicate, papery flowers, and aromatic leaves. These shrubs are hardy, drought-tolerant, deer-resistant, and withstand extreme heat. They grow well in poor-quality soils and often survive in locations where other plants can’t. A great addition to rock gardens and exposed garden beds, rockrose is best planted in the early spring. You can find these Mediterranean flowers growing naturally in coastal areas and dry banks alike.

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 groundcover 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. Here are the basic requirements for growing rockrose:

• Plant in full sun.
• Provide a site with well-draining soil.
• Establish new plants with an initial feeding of slow-release fertilizer and a regular watering schedule.

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, following product label instructions. After they are established they 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 wide
• 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

Rockrose 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 moist 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 is the Mediterranean winter climate they are accustomed to.

If your region 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 it 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

Among the most ornamental of all Mediterranean flowers, rockrose is known to produce showy blooms that resemble hibiscus.

Bloom Months

In most areas, rockrose typically blooms in the summer months of June, July, and August. They can start blooming as early as the first signs of Spring and continue to bloom as late as the first heavy frost.

How Long Does Rockrose Bloom?

Rockrose blooms last just a few hours before they drop. You can expect new flowers to open the following morning.

What Do Rockrose Flowers Look Like?

Rockrose blooms are generally 2 inches in diameter and can be pink, white, or yellow. Depending on the cultivar, some have a distinctive brown or reddish blotch at the base of each petal which can be described as delicate and crinkled.

How to Encourage More Blooms

Failure to bloom is usually due to lack of sunlight, or excess nitrogen, which will make the plant grow abundant foliage but no flowers. Feed the plant with a bloom-boosting fertilizer that is high in phosphorus to encourage more blooms. Ensure that it is receiving plenty of light.

Caring for Rockrose After it Blooms

Once the flowers fade, prune lightly to preserve the buds that form next year's flowers. Resist any heavy pruning as weak branches may stop bearing flowers in the future.

Deadheading Rockrose Flowers

There's no need to deadhead rockrose blooms because they will fall on their own after a short time. You only need to gently prune once the flowering season ends.

Common Problems with Rockrose

Rockrose has relatively few issues. When these plants struggle, it is more commonly due to unsuitable growing conditions rather than other factors.

Leaves Turning Yellow

If your leaves are turning yellow and wilting, it could be a sign of root rot. To prevent this, avoid poor water management, mainly too much water or irrigation often caused by soil with inadequate drainage. Rockrose plants do best in dry conditions but should not be overwatered.

Leaves Turning Brown

This could indicate frost damage. Make sure your plant is not in an exposed location if you have a very cold winter. If growing in a container, be sure to bring it indoors during the months when frost is expected. Also, be aware that early spring frosts can still occur which can damage potential blooms.