Arilbred and aril irises are basically bearded iris species that are native to the extremely parched regions of Turkey and Israel. These irises include the Regelia and Oncocyclus iris species, in addition to the Arilbreds, which are actually hybrids developed by crossing the tall bearded irises and iris species belonging to the groups mentioned above. Aril irises have derived their name from a little white aril or a collar-like fleshy appendage of their seed. Generally, it is quite difficult to grow arils in temperate climatic conditions, as they have a propensity to be vulnerable to rhizome soft root and rust. In case you do not spray these plants regularly, it is likely that you will lose them soon. Aril irises grow successfully in areas receiving poor rainfall like the places of their origin.
Arils are somewhat dissimilar from the other bearded iris species. These plants bear delicate, rather insignificant leaves that do not have any sheen or vitality - very different from the verdant green leaves of the normal bearded iris species. On the other hand, the blooms of arils are really amazing having many interesting shapes as well as color patterns. In fact, the flowers of Regelia and Oncocyclus irises are very different from the other varieties of bearded irises. While the flowers of the standard bearded irises are rounded, quite large and nearly closed together when compared to their falls, which usually recurve or bend backwards below the flowers.
Normally, the colors of aril blooms are extremely pure as well as clear. Alternatively, their blooms may even have wonderful blotches that contrast the color of the flowers. When arils are hybridized with the standard bearded irises, the progenies retain a number of these attributes, while some other progenies may have new, but mesmerizing hues, patterns and streaks.
Iris susiana, which is sometimes referred to as the morning iris owing to its sober hues, is perhaps the most familiar Oncocyclus iris species. I. susiana is also the easiest Oncocyclus iris species to grow. Having its origin in Syria, although I. susiana have been grown for about four centuries, it has never been spotted growing in the wild. The flowers of this iris species are large and they overlook the foliage. The blooms have very unusual colors, but the falls and standards are normal - having a creamy gray backdrop. The flowers of I. susiana are not only heavy, but also have dense deep purple-brown veining. While the signal or landing stretch on the falls is very velvety having a ruby-black hue, the beard of the flowers has a dark purple-bronze color.
While the arils and arilbreds have very sparse beards, those of arillate irises are quite substantial. The beards on the blooms of the Regelia iris species are long and appear scraggly. Those of the Oncocycluses look like a broad hairy patch. These species are generally hybridized with the tall bearded irises. They are also crossed with the median as well as miniature dwarf bearded irises.
When we talk about aril irises we denote all the iris species as well as hybrids having arillate seeds - seeds with small fleshy collar-like appendages that are known as "arils". This is actually a botanical attribute of this iris variety. Likewise, the word "arilbred" denotes all hybridized irises that originate from crosses between the aril species as well as the aril species hybrids with true bearded irises (also called eupogon).
There are about 50 Oncocyclus iris species, which are commonly referred to as oncos, characteristically have overlapping standards with a round, arched appearance. The standards of oncos may be ruffled, tailored or even reflexed externally on their sides - an attribute that is also known as flagging. The falls of oncos are also rounded and are generally pushed beneath the flowers. The falls of this iris variety may be rolled under, recurved, concave, flaring or even some kind of mishmash of these characteristics. Usually, the standards are larger compared to the falls.
The height of the flowering stems of arils and arilbreds varies greatly - ranging from just 3 inches to about 28 inches. Each stem bears a solitary flower. Generally, the proportion of the flowers to the stems is good, but there are always some exceptions - large flowers appearing on very small stems or small flowers attached to very tall stems. The flowering stems of arils and arilbreds are more or less erect. Some stems may have leafy spathes. While some stems may be broad and plump, there may be others that are slender and sinewy.
The falls of aril flowers have another typical characteristic. They may have veins and dotting or stippling in subdued or strong shades. These features may also appear in the standards of aril flowers. The dark, circular spots, also known as "signal", which appear at end of the broad beard are another typical trait of the flowers of Oncocyclus irises, which distinguishes them from other iris blooms. Usually, the beards are wide, but some may also be thin and straight. The color of the onco beards may vary, ranging from white to almost black. The flowers of this iris variety also come in an assortment of colors, textures and patterns, which may include self, amoena, bitone, blend, and bicolor.
Each stem of the Regelia irises belonging to the aril class generally bears two flowers. The standards and falls of the Regelia irises are slender compared to those of the oncos. Sometimes, the standards of Regelia irises are pagoda-shaped. The standards as well as the falls of the Regelia irises are intensely veined. The beards of the Regelia irises are slender as well as vividly colored, which occur mostly on the falls, and to some extent even on the standards. Provided there is a spot or "signal" at the tip of the beards arising from the falls, generally it is small and appears in the shape of a V and it is a colored spot. Compared to the oncos, the flowers of the Regelia iris species appear more delicate and their size varies from small to medium. The flowering stems are thin and rather tall compared to the size of the blossom.
Usually the iris crosses developed by hybridizing the Oncocyclus iris with the Regelia species have two buds on each stem. The influence of the Regelia species is more prominent on the flowers of the progenies of these two species. As a result, most of the traits of these flowers are similar to that of the Regelia irises, such as intense veining, color spots and a V-shaped "signal". Hybrids iris flowers having lilac or lilac-rose hues will have deep violet or greyish-purple veins in addition to a dark signal spot. The size of these plants as well as their flowers will be medium.
First and foremost, you need to decide on an area in your garden having excellent drainage and receiving lots of sunlight. Moreover, the soil ought to be suitable for growing the tall bearded iris species or the median bearded irises. Remember, gardens having too heavy soils or receiving abundant rainfall are not suitable for cultivating these species, as these conditions result in root rot in the tall bearded irises and also will cause problems for the arilbreds too.
Having an excellent drainage is extremely vital as it will go a long way in ensuring that the plants thrive well. In fact, you should grow the aril and arilbred irises on raised beds if the soil in your garden is heavy, the drainage is poor or there is excessive annual rainfall. In fact, arilbreds can endure rainfall that is several times more than the average in the native land of arils. However, this is only true if the drainage in your garden is excellent. In some regions the best way of growing arils and arilbred irises is to plant them on raised beds having soils that have been specially prepared.
It is essential to get the iris bed ready several weeks before the actual planting. It needs time to mix the soil with fertilizer and water the area allowing the soil to settle down. When you are set for plantation, dig two holes in the bed separating them by a slender edge. Subsequently, press the iris rhizome into the ridge. Ensure that you stretch the roots or the rhizome to both sides as well as downwards. When this done, pack the hole with soil, ensuring that no air pockets exist in the region of the rhizome as well as its roots. The top portion of the rhizome should ideally be roughly 1 inch to 2 inches under the ground level if the soil is heavy and anything between 2 inches and 3 inches under the ground level if you are planting the rhizome in sandy soil. The plants should be placed no less than a foot from each other.
Ensure that the area around the root is moist, but not wet all through the growing season of the plants. At the same time, check the soil at regular intervals to about 3 inches or 4 inches deep for moisture. It is advisable that you also use a standard fertilizer once in the fall and again at the onset of spring. In fact, arilbred irises are notorious for being heavy feeders. Therefore, it is important that you remain steadfast on your fertilizer program. It is also necessary to get the soil in your garden tested to find out if it lacks any nutrient. You can actually decide on an effective fertilizer program after testing the soil. In case the soil in your garden is neutral or acidic, you should increase the pH level of the soil by adding dolomitic limestone. Adding dolomitic limestone to the soil will promote the growth of irises, while lessening the chances of rot. When the irises are in bloom, you need to take care of the plants as and when necessary subject to the climatic conditions in your area. In case the summers are very dry in your area, you should discontinue watering the plants and allow the plants to remain in the ground. Compared to other bearded iris species, arils and arilbreds have a preference for soils with an elevated pH level.
Ideally, arilbred irises should be planted when they are just getting out of their hibernation or dormant period. You should avoid planting irises during the summer heat, as it is very stressful at this time of the year. Similarly, irises should not be planted during the late fall just before the harsh winter months. In fact, the best time for planting irises is actually subject to the climatic conditions in your region. When the summer heat is intense you should leave the plants in the ground to lie dormant and plant them when the severity of the climate is over and the arils are just beginning to come out of their dormancy. In case, you are planting new rhizomes, plant them along with the older arils at the same time.
As far as dividing the irises is concerned, you should know that several arils as well as arilbreds multiply very quickly and these need to be divided once every year or in two years with a view to prevent the plants from getting too crowded. It is suggested that you follow the same digging and planting schedule immediately when the severest summer heat is over and there is still enough time for the rhizomes to grow new roots before the arrival of the harsh cold during the winter months.
