Cistus ladanifer (Gum Rock Rose)
Cistus ladanifer, commonly called Gum Rock Rose, is a large erect evergreen shrub with dark green glossy leaves and solitary white flowers, usually with a dark maroon spot at the base of each petal and a crumpled tissue paper appearance. Each flower only lasts one day, but new ones bloom every day during the spring and summer.
It is a drought-tolerant shrub native to the Western Mediterranean basin, specifically to Southern France, Spain, Portugal and North Africa.
Due to the wide distribution and morphological variation of this species, there are 3 recognizable subspecies:
- Spp ladanifer (Portugal, Spain, South France and North Morocco)
- Spp africanus (South Spain, North Morocco and North Argelia)
- Spp sulcatus (South Portugal)
HEIGHT & WIDTH
Gum Rock Rose scientific name
- Botanical name: Cistus ladanifer (SIS-tus ladan-i-FER)
- Family: Cistaceae (SIS-TAY-see-ee)
- Common name: Gum rockrose
|Cistus||Comes from the Greek word “kisthos”, meaning box, basket. Related to the shape of its fruits.|
|ladanifer||The name literally means “bearing of ladanum”, which is the sticky gum that this plant exudes from the stems and leaves.|
How to identify Cistus ladanifer
Cistus ladanifer is an evergreen, dense and upright shrub slightly narrower than wide. It has dark green shiny leaves and large solitary white flowers.
Due to the ladanum (resin) exuded by the new shoots and leaves, the shrub is very sticky, shiny and fragrant, especially in hot weather.
It usually reaches 2 m in height (6.5 ft) or more after 5 to 10 years. The width can range between 1 to 1.25 m (3.2 to 4 ft).
The stems are greyish-brown and shiny with no hairs. The leaves are opposite at each node, and the flowers are solitary at the end of the stems.
The stem and leaves have a sticky substance called labdanum, which is a strongly fragrant resin that adheres easily to hands and clothes.
The leaves are shiny and dark green on top. Underneath, they are greyish with glandular hairs that produce the aromatic sticky gum called labdanum.
They have a linear-lanceolate shape, 40-80mm (1.6 – 3.2 in) long, and 10-20 mm (0.4-0.8 in) wide.
The leaf is scarcely stalked. It has three prominent veins at its base (especially in the subspecies sulcatus)
The flowers are solitary and large. The ladanifer species has the largest flower of all the cistus.
They are white and often have a maroon blotch at the base of each petal. However, sometimes these maroon spots may not be present, and the petals are completely white (as in the case of subspecies sulcatus).
Each flower has 5 petals with a crumpled tissue paper appearance and 3 sepals. At the centre are numerous orange stamens and one pistil.
The flower size is around 7 to 10 cm (3 to 4 in) in diameter.
The flowers usually bloom in spring and summer but last only one day. They open early in the morning, and the petals fall shortly after midday. However, new flowers bloom every day for many weeks.
The fruit is an ovoid hairy capsule inserted in the calyx. It opens into 5 to 10 valves containing a large number of seeds.
The fruit size is 0.7 to 1.3 cm (0.3 to 0.5 in).
The seeds are very small, 1 to 1.5 mm (0.04 to 0.06 in), and have a hard, water-impermeable brown coating.
Quick tips to identify Gum Rock Rose
Cistus ladanifer Usage
The Gum rockrose is a very popular ornamental plant due to its beautiful and delicate flowers and its strong scented shiny foliage.
It can be used as a solitary plant or planted in groups with other types of Cistus or other drought-tolerant plants. In beds and borders. In rock or gravel gardens. They are particularly interesting for drought-tolerant and low-maintenance gardens.
Different parts of the Cistus ladanifer have varied culinary uses.
The seeds can be ground into flour and used for baking cakes and bread.
The resin obtained from the shrub is used in food flavouring, ice cream, chewing gum, etc.
The fragrant resin secreted from the glandular hairs on the bottom of the leaves is used in diverse cosmetic products, such as perfumes, soaps, skin creams, etc.
Cistus ladanifer has been used for centuries in traditional medicine. But research has also demonstrated its therapeutic potential with analgesic, antibacterial, antifungal and antioxidant properties.
It is also used in aromatherapy to alleviate stress.
Reforestation of dry regions
Cistus ladanifer is a very robust plant surviving prolonged heat and droughts. It can also quickly regenerate after wildfires which makes it interesting for reforestation after forest fires that burn all the existing vegetation.
During the growth period, the plant drops its seeds in the soil, and these can remain dormant for long periods of time. However, the intense heat of the fire causes the seed coat to crack, and the surviving seeds germinate shortly after the fire.
Some people say that where it is seen in the wild is a good indicator of the soil quality since it prefers poor soils.
Cistus ladanifer is a melliferous flower with lots of pollen that attracts bees, butterflies, and many other insects, enriching the biodiversity in your garden.
The roots of Cistus shrubs have the ability to create a mycorrhizal relation with truffle mushroom fungi. In this relationship, the truffles provide nutrients to the Cistus in exchange for carbohydrates.
Several studies are analysing their possible usage as host plants for truffle cultivation. The advantage is that Cistus shrubs are much smaller than traditional hosts such as oaks and pines, leading to higher production for the same area.
It is also a good nurse plant for sheltering young seedlings.
What does Cistus ladanifer flower symbolize?
In the popular culture of some Mediterranean countries, the red dots on the five petals of the Gum Rock rose flower symbolize the five wounds of Jesus Christ.
How to plant and care for Cistus ladanifer
Cistus plants are native to the Mediterranean basin, so they are adapted to hot, dry summers and mild, moist winters. Usually, they are not very hardy; however, Cistus ladanifer is one of the hardiest species and can tolerate temperatures down to -12ºC (10ºF) as long as the soil is sufficiently dry.
However, when the plant is not yet established, it will need winter protection during the first few years. You should cover the root area with mulch to protect the roots from severe frosts and very low temperatures.
Cistus ladanifer likes poor, well-drained, light sandy soils. It can tolerate most types of soils but prefers acidic ones.
This shrub needs full sun to thrive and does not like to be watered.
Cistus ladanifer is a very robust plant and usually does not have problems with pests and diseases.
The best time to plant this shrub is at the beginning of spring for colder regions or the beginning of autumn for warmer regions.
How to water Cistus ladanifer
Cistus ladanifer is a drought-tolerant plant and does not like humid soils. Once established it no longer requires watering.
During its evolution, it developed mechanisms for drought tolerance:
- Dense hair in the branches and leaves to trap moisture
- Symbiotic relationship with mycorrhizal root fungi provides water and nutrients in exchange for carbohydrates.
During the first two years after planting, you will need to water the young Rock rose every two to three weeks during the summer. Allow the soil to dry out between watering.
When watering it, you need to do it abundantly, giving the soil a generous soak so the water can penetrate deeply into the soil to allow the roots to grow deeply.
To preserve the soil´s moisture, you should add mulch around the root area of the Rockrose (but not too close to the base). Wood chips and gravel are good options for mulching.
How to prune Cistus ladanifer
Cistus ladanifer does not require any pruning. Actually, it does not like being pruned or having its roots disturbed, especially as it ages.
So any pruning should be limited to the removal of dead or damaged stems at the beginning of spring.
How to propagate Cistus ladanifer
Propagation by seed
Rock roses can be propagated by seed, but it is not easy.
Seeds in the wild germinate easily after wildfires, so it may be useful to give them a heat treatment to facilitate their germination.
The seeds usually germinate within 1 to 4 weeks at around 20ºC (68ºF).
Keep them in a greenhouse during the first winter and then plant them in their final position during the following spring.
Propagation by cuttings
The easiest method of propagation is by cuttings.
Softwood cuttings Take these cuttings, 8cm long with a heel or at a node, from a non-flowering shoot, in early summer. Roots will form in up to 4 weeks.
Semi-ripe cuttings can be taken from late summer to late autumn. Take an 8cm cutting with a heel or at a node from the current year’s growth. Roots will form within 4 weeks. Semi-ripe cuttings can be placed in a cold frame over winter.
Hardwood cuttings taken in late winter, just before new growth starts, will root easily. Cuttings can also be taken in mid-autumn from the current year’s growth. Take a cutting 8 to 12 cm long with a heel or at a node.
Since cistus plants do like root disturbance, especially as they get old, they should be planted in their final positions while still small.
Other Cistus you may also like
Sources of information used for this article
Article from RHS site
Article from Useful Temperate Plants database
Article from Naturdata
Article from University of Evora
Article from Biodiversity4all
Article from Wilder
RHS Propagating Plants: How to Create New Plants For Free by Alan Toogood and Royal Horticultural Society
Field Guide to the Wildflowers of the Western Mediterranean, Second edition Paperback – 1 Oct. 2021 by Chris Thorogood