Scorpio Or Juno Irises

Imagine a plant with foliage that grows up the stem in alternating steps, rather like young leeks or corn, and you will have a picture in your mind of what juno irises look like. In fact, their appearance is so different from other irises, there is talk of classifying them in a genus all their own. It is a large group, comprising over 50 species, but few of them are commonly grown. They are natives of arid regions with extremes of climate in central Asia and around the Mediterranean. As you would expect from their native habitats, they are frost-hardy (to 10°F/12°C). The flowers, of unusual form, grow out of the leaf axils with standards unrecognizable as such. Either they are horizontal or they point downwards like stiff little wings, while the style arms appear to take the normal position of standards. The falls may be horizontal or held upright at an angle of about 45 degrees. When cutting Juno irises for indoors, take as few leaves as possible to avoid weakening the bulb.

Juno irises have thick-necked bulbs clad in thin brown tissue with fleshy white roots -like long radishes -that extend down and out into the ground. These roots are replaced each year so that an undamaged bulb, when it is dug up, will reveal both old and new sets at the same time. Handle the bulbs with care as the new storage roots are brittle and precious. In the fall the fleshy roots send out another set of roots, fibrous in texture, which start the annual growth cycle.

These irises are easy to grow so long as a few main points are kept in mind. Excellent drainage is very important. A raised bed in full sun, filled with a mixture of half sand and half soil, is ideal. They are suitable plants for containers as they don't like being disturbed. In theory, they are supposed to be kept quite dry during summer dormancy, and in pots it is easy to move them under cover once flowering is finished.

They relish a top-dressing of lime and blood meal or well-rotted animal manure in the fall.

Because the plants are often hard to source, it may be necessary to grow juno irises from seed. They take about four years to have flowers.

Culture

Full sun is a key to growing healthy juno irises. Those juno irises that are native to the dry steppe and mountainous country of Asia are used to a continental climate, one noted for cold winters with lots of snow and summers that are hot and dry. Juno irises that are originally from warmer Mediterranean areas are tender and can't survive freezing weather.

These irises, after blooming in the spring, prefer to estivate (go dormant) in the summer. The blooming time, which will depend both on the species and on the climate, runs from April through May and even June. Climates that have humid to wet summers are not conducive to the health of juno irises. Some gardeners who are successful in growing junos in such places have had good luck in growing them by cutting off all water, even roofing over the beds to keep rain diverted.

The soil should be that of the native lands, which ranges from sandy to heavy soils depending upon the species. The juno irises do not seem to tolerate acid soils well, preferring soils that are higher in pH such as those that are from regions with limestone bedrock. Gravelly or sandy soil seems to bring success in growing most of the bulbous irises.

If you are growing juno irises in containers, use a soil mix that drains well and beware of overwatering. One key to successful pot culture of junos is to water from the bottom, allowing the potting medium to get nearly dry before rewatering. Excess moisture is one of the biggest problems in growing junos.

Winter care for juno irises grown outdoors should include a straw mulch or the equivalent, especially for seedlings. The mulch will help protect the plants from the freeze-thaw cycles that are so destructive. Plants that can stand extreme cold are often severely injured if there are unseasonal warm spells followed by hard cold snaps.

Species

I. bucharica

This iris is probably the best-known of the junos. It will grow up to 20 in (50 cm) but is usually smaller. Rather like the blooms of gladioli, flowers open from the top down, with large bulbs producing as many as eight in succession. Standards and falls are creamy yellow and the broad upright crests are white, as are the style arms. This iris flowers about the middle of spring.

I. persica

Iris, which comes from Iran and Turkey and flowers almost at ground level in late winter and spring with a wide variation of color in its flowers -greenish blue, white, yellow, red-purple or violet. Although it has been cultivated for centuries it is not widely grown or easily available.
It is, however, important as one of the parents, with I. aucheri (syn I. sindjarensis) , of I. 'Sindpers', which is a vigorous grower and has flowers of a lovely cool hue between slate-green, pale turquoise and gray. Growing to about 4 in (10 cm) high, it flowers early in winter.

I. magnifica

This iris is robust and one of the more commonly grown junos, good for a sunny rock garden. It is a taller species, growing between 12-24 in (30-60 cm) high, with flowers in pale lilac and yellow. Wide wings feature on the haft of the falls that act as drainage channels to take moisture away from the ovaries.

I. warleyensis

This iris comes from Bukhara in Uzbekistan, is hardy, bears narrow foliage and has attractive flowers of lilac, with a sharply defined pattern on the falls of white, dark purple and yellow.

I. willmottiana

This iris is a robust, short plant 6-10 in (15-25 cm) high and at flowering time the stem is packed with about eight broad, shiny leaves which gradually elongate.
The flowers are soft lavender or pale purple with deeper lavender and white on the falls. It also bears the drainage wings on the falls that are a feature of some of these irises.

I. cycloglossa

This iris is one of the easier junos to grow. Its flowers, appearing late in the season, are rather like the shape of Xiphium blooms with large erect standards. They are perfumed with the scent of cloves and are a bright purple-blue. It is usually described as having one to a few branches, each bearing one or two flowers.