Botanical/Latin
Iris sibirica & ensata
Pronunciation
eye-ris
Common Name
Siberian & Japanese Iris
Hardiness zone range
4 - 9
General Comments
These have narrow sword-shaped leaves
and the familiar iris flowers, but without the
"beard". They flower after their bearded cousins,
with the Siberians flowering first and the
Japanese (I. ensata) flowering later in
summer.
By making careful selection and
meeting the required cultural conditions, it is
possible to have a succession of irises flowering
from late spring to summer.
Uses
Excellent for beds and borders near water features, ponds, pools, streams, bog gardens or damp spots.
Light Preference
Sun. Iris sibirica (once
established) will tolerate and flower reasonably
well in partial shade. The best results will be
obtained when they placed in sunny positions with
more than six hours of sunlight; this is
particularly important with Japanese Iris
(I.ensata).
Culture
Both types succeed best in deep,
rich fertile soils that remain moist and have a pH
that is on the acidic side of neutral. The
Siberians are more adaptable; they will tolerate
occasional drier periods and soils that are on the
alkaline side of neutral.
This
adaptability, coupled with their ease of culture,
graceful foliage and beautiful blooms makes them
popular garden perennials.
The Japanese
type (I. ensata) have gorgeous, sometimes
enormous, blooms. They need more exacting
conditions. They are heavy feeders and respond to
having organic matter like manure, compost, etc.
added at planting time and a fertilizer dressing
applied in spring and again after flowering.
Mulching also helps to retain moisture and improve
soil conditions. The pH level is more critical
with these; it needs to be slightly acidic (pH
5.0-6.5). At levels above this, they may develop
yellowing in the foliage and have reduced vigor,
so efforts will need to be made to reduce the pH
and correct Iron chlorosis.
Background
The genus Iris was named after
the Greek goddess who used the rainbow as her
pathway to the heavens. Legend tells us that when
she visited earth the flowers that bear her name
sprang up in her footsteps.
Cultivated
since ancient times as plants of economic
importance, some of the bearded types were used
as medicine and dried as orris root for the
cosmetic and perfume industry. This fabulous plant
family has won the admiration of many cultures and
races. This appreciation has been passed down
through the annals of time to the present day. New
selections and hybrids are constantly added to the
many thousands of cultivars already in existence,
so take your pick and enjoy them; they're
wonderful.
Splendor Suggestions
Where the garden soil conditions
are not suitable (alkaline or too dry) and to
admire the flowers at close quarters, consider
growing a few I. ensata in containers. Select a
suitable container, fill it with an appropriate
acidic compost, water and fertilize, making sure
both are lime free. As the buds are opening, move
the pots either indoors or into a sheltered spot
where they can be enjoyed and
appreciated.
In Japan, large flowering
types have been grown in this way for centuries.
It is a wonderful experience to watch the buds
unfold into dramatically beautiful patterned
flowers.
Companion Plants
Absolutely magnificent when
massed with Astilbe cultivars. The colors and
feathery flowers blend well together. Pleasing
effects have been achieved in borders or curving
beds, when a transition of color starts with bold,
dark shades gradually becoming
paler.
Ajuga `Burgundy Glow' with its
tri-colored variegation and blue flowers and
Corydalis 'China Blue' or Lamium `Shell Pink' make
wonderful ground cover and edgers. The frosty blue
leaves of Hosta `Krossa Regal', `Halycon', `Blue
Angel' or the smaller growing `Blue Cadet' look
well also. Those with white variegation like H.
undulata `Undulata', `Albo-marginata' or `Patriot'
soften and compliment the darker colors.