all the article and a lot of other types of ladanum in link : http://www.mediterraneangardensociety.org/plants/cistuskm.html
by Ken Montgomery
I confess to a love affair with rockroses that
has lasted almost thirty years. These fascinating
and extraordinarily beautiful plants bring a long
list of desirable qualities to the world of
Most rockroses are extremely drought-tolerant.
Once established they require minimal irrigation in
the dry season and can contribute significantly to
water conservation efforts. Gernerally speaking,
these shrubs are cold-hardy to temperatures as low
as 5°F., adaptable to a wide range of soils and
microclimates, easy to grow and maintain and
resistant to serious pests and diseases. Many have
extensive root systems, making them useful in
stabilizing slopes and controlling soil erosion.
They provide cover for wildlife and are compatible
with [California] native vegitation. At the same
time, they are not invasive and pose a minimal
threat of spreading into natural areas and becoming
pests. Low-growing kinds are somewhat
fire-retardant and many others are unpalatable to
The common name "rockrose" referes most
often to the members of three closely related
genera - Cistus, Halimium, and Halimiocistus.
These groups are classified together in the family
Cistaceae along with sunroses (Helianthemum).
Rockroses are so called because their flowers
resemble single, old-fashioned roses (although
they are unrelated) and because they prefer to
grow in rocky, well-drained soil. They are
evergreen strongly woody shrubs, varying in
height from two to over eight feet and from three
to more than six feet across. Some sprawl on the
groun, while others are open, erect and rangy.
These are not plants for formal, highly structured
gardens. Even with moderate pruning, rosroses
have a wild, undomesticated look in the landscape.
They bloom most heavily in the spring, with some
species beginning as early as March. Each flower
lasts only a few hours but many kinds bloom so
profusely that the entire plant is covered with
hundred of new blossoms each day. Colors range
from white and many shades of pink and
lavender-pink in Cistus to white and yellow in
Halimium. Flowers of some rockroses also have a
showy red to maroon spot or blotch at the base of
each petal, offering stunning contrasts to the
numerous bright yellow stamens at the center.
All rockroses are native to lands surrounding
the Mediterranean Sea. They are adapted to long,
hot, dry summers - the same conditions found in
much of California. As we begin facing the reality
of a semi-arid Mediterranean climate here in
California, the use of appropriate plants in our
gardens and landscape takes on increasing
importance. In this context, rockroses are enjoying
greater popularity than ever before. Old faorites
are being rediscovered and many fine new
selections are being introduced into the nursery
trade. The future is bright for rockroses, and I
couldn't be happier!