Bearded Irises

One of the oldest iris varieties, the bearded irises can be often found adorning your grandmother's garden. These irises are also known as flags or German irises. In fact, a noted 18th century Swedish botanist named Carolus Linnaeus was the first to name the tall bearded irises their binomial scientific name Iris germanica. In 1753, Linnaeus published his work on botanical taxonomy called "Species Plantarum". In fact, this book was the first to explain binomial nomenclature that all of us use today. Nevertheless, Linnaeus made some mistakes in naming Iris germanica, whose sample was sent to him from a German garden. In Germany, this plant is never found growing in the wild. Precisely speaking, the plant Iris x germanica is actually not a species. Instead it is possibly a natural iris hybrid that grows up to a medium height. For the sake of records, the entire predecessors of the bearded irises have their origin in eastern, central and southern Europe as well as the Near East. In fact, role of the bearded irises has been vital for the family Iridaceae for such a prolonged period that details regarding the origin of this much loved perennial plant are covered with the haze of time. It is possible that several iris species were crossed with other species naturally mainly owing to the closeness of these plants. In addition, it is also possible that even the early growers have been hybridizing irises since several centuries back. It is highly possible that in the initial stages of iris breeding the process involved choosing attractive irises developed from crosses that occurred due to pollination by bees, instead of the artificial pollinations undertaken by humans in present times. Nearly all taxonomic botanists are of the view that the present day bearded irises came into existence following cross-breeding among the 14 different iris species found in the wild, which includes albertii, mesopotamica, gatesii, cypriana, variegata, kashmiriana, trojana and pallida. As the size of the progenies varied following such breedings, currently the bearded irises have been categorized into six distinct groups, depending on their growth habit as well as plant size.

Plant characteristics

All bearded irises are basically elegant plants. Irrespective of whether they are tall or short, flowers produced by all bearded irises have stately forms. The plants emerge from a rhizome and have fans of bluish green leaves that are sword-shaped, and sculptured. These leaves may be stiff and erect, or curve stylishly at the tips. Some varieties of bearded irises produce leaves that may have an amazingly beautiful purplish-red shade at their base. If the leaves are coated with a wax-like substance, it signifies that the plants are in excellent health. The healthy plants will bear strong leaves with a bluish dash and grow robustly right from the center of the fans. The rhizome (actually a distended stem) of the iris is the place where the plant accumulates moisture and nutrients for use during unfavourable conditions. These stored substances also help the plant to endure some amount of stress. The growing season of the plants occurs during spring, just after the flowering season. Generally, the growing season of irises lasts for about a couple of months. The plants take some rest or lie dormant during the middle of summer. Fresh growth occurs again during the fall, just before the leaves wither away and the plant again goes into a dormant period for the cold winter months. The rhizomes of irises grow horizontally all along the soil surface and giving rise to leaf fans upwards, while sending the roots down from their budding end. The rhizomes become tough as the summer heat increases, thereby protecting the moisture and nutrients stored inside them. At the same time, the hardened surface of the rhizomes prevents pests as well as diseases from getting inside. Nevertheless, prolonged wet weather conditions, such a long spells of rain, may make the rhizome soft as well as weaken it. This is the time when slugs and various other pests gain easy entry into the rhizome and have a good meal. Every year, the iris rhizomes divide as well as multiply naturally, gradually forming an intricate interwoven mat. In order to make sure that the plants produce enough flowers every season, it is essential to divide the irises before they enter this phase. In fact, an iris rhizome only blooms once each season and subsequently develops new rhizome just behind the flowering stem of the present season. Occasionally, they also grow new rhizomes from the buds along their length. Increasing in this manner enables the plants to avail more nutrients from newer soils. In fact, the leaf fan of irises is the sign of the growing point. It is from here the new plant moves away from the worn-out mother rhizome. Different varieties of irises grow as well as increase at different speeds - at times producing a great number of new plants every year, while there are some other varieties that produce relatively fewer new plants annually.

Flower characteristics

Similar to all other iris varieties, the flowers of bearded irises have three falls, three standards and three style arms - the number three being important in the case of all irises. The standards of bearded irises have a graceful dome shape and they close up above the blooms, shielding the style arms. Usually, the style arms of bearded irises come in attractive hues. The female portion of the bearded iris blooms, also known as the stigmatic lip, lies under the standards, while the anthers that contain pollens (the male elements of a flower) are concealed just below the stigmatic lip. The lower petals of bearded irises, which are also known as falls, curve both downward and outward, displaying the beard. The falls are rather akin to a large hairy caterpillar - the key distinguishing trait of bearded irises. The beards of this group of irises have several different colors - sometimes their color is same as the flower, which presents an intense effect in general. An excellent example of this is the "Night Rider", which has intensely ruffled purple-black beards. In addition, the color of the beards may also be completely different from the flower, as in the case of "Stately Art", where the gorgeous blue flowers are aptly complemented by an amazing red beard. Beards actually contribute to the charm and character of the blooms, augmenting as well as complementing the hues, especially during the fall. In the case of a number of hybrid bearded irises, the beards may also come with horns or extensions as well as other attractive appendages like flounces and spoons. In fact, "Mesmerizer," a white bearded iris comes with lacy flounces which make it appear like a double flower. On the other hand, "Thornbird" has a bizarre tan hue and it comes with noteworthy dazzling violet horns. Irises that have such unusual traits are called "Space Age" irises. The falls of bearded irises may have various shapes and forms. They may be smooth, frilled or ruffled; narrow or broad; and sometimes they may even stick out prominently like a saucer; droop downwards gently or recurve beneath the bloom. After they open up, the bearded iris flowers will stay in excellent condition for more or less three days, subject to the temperature outside. Removing the spent flowers is quite simple, as they close after blooming. To remove the spent flower you first need to hold the base of the new bud firmly and turn the spent flower downward and away carefully with a quick movement. This will make the spent flower snap from the socket without any problem. Even the color patterns of bearded iris flowers differ greatly. While some flowers have only one hue, there are others that come in multiple colors, including veining, streaking as well as thumbprints. Specials names have been assigned to indicate specific color patterns. For instance, a single color is referred to as a "self". In fact, "Blenheim Royal" is a good example of a true, vivid, purple "self". In an ideal condition, bearded iris' flowering spike should bear a minimum of two branches having stems and branches and producing many flowers. It would be best if a good flower spike has branches that curve outwardly from the main stem and supports the blooms in a balanced as well as erect manner - very much different from that of a candelabra. It will be called a perfect situation when three flowers open simultaneously in a balanced manner and at a uniform space, the length of the spike. Thumbprints are quite common in dwarf bearded irises. This variety of bearded iris comes in thumbprints that have rich contrasting hues just under the beard. However, this is a new pattern, which is just starting to materialize in the irises belonging to the bearded group.

Flowering spike

Selecting the foreground as well as the background for the bearded iris has a direct relation to the plant's flowering spike. Like there are a variety of popular characteristics in plant habits, the flower spikes of the plants too have a number of desirable attributes. Some of these traits are discussed briefly below. Strength: Ideally, the flower spike ought to be strong, capable of supporting the flowers properly and also be suitably inflexible with a view to make sure that the winds will not blow it away. In fact, any good quality iris is one that never requires a stake in the garden. Proportion: The flower spike should be in right proportion to the plant's foliage. In fact, the spike ought to be quite toll so that the flowers are always on top of the foliage to make them clearly visible. In addition, the branches comprising the spike ought to be spaced evenly along the flower spike. Presentation: Another important characteristic of a desirable flower spike is that it should be properly branched and each of the branches should have the aptitude to display the flowers elegantly as well as in a neat manner. In addition, all the branches should ideally have numerous branches to make sure that the flowering season is quite prolonged - preferably each branch should have not less than three branches and six flowers. Some iris species/ cultivars are just as satisfactory if they bear less number of buds on the flower spike, but carry multiple spikes from the rhizome. "Vanity", an attractive pink iris, is an excellent example of the latter iris type. Often, this traditional beauty bears just four buds on a spike, but sometimes, it can send up as many as three or even more spikes from just one rhizome. In addition, it is also important to have a harmony of the blooms appearing on the spike's different branches. It is possible that one flower may open on each branch at the same time, presenting a wonderful display of colors and making the spike ideal for showing. On the other hand, the flowers on different branches of the spike may also open from time to time, thereby prolonging the flowering period in a garden. The pace at which the flowering spikes come out from the foliage may often be amazing. You can often tell if a plant will flower by judging the visible curve in central leaves of the foliage fans. However, this guide is not a perfect one. You can also confirm the presence of the flower spike by lightly feeling the base of the foliage fan. In its initial stage of growth, the flower spike can be frail and even breakable. Therefore, it is essential to exercise extra caution so as to prevent breaking the spikes, particularly when you are trying to feel it or while weeding. Hence, it is very important to always keep the area where you are growing irises free from weeds, especially before the flowering season of these plants. When the flower spike has grown up to its full height, the speedy change in its looks slows down. At this stage, the flowers increase in size. The time period between the coming out of the flower spike and the beginning of flowering differs very much. However, often it can be below two weeks.


The older iris rhizomes located in the hub of a clump usually become unproductive after growing for about two or three years. Division and transplantation of irises are necessary to sustain the vigour of the plants. Ideally, division should be undertaken soon after the flowering season, at what time the white fleshy roots are easily noticeable beneath the leaf fan signalling the growth phase of the plants. If the plants are divided during this period, they will be able to re-establish themselves quickly. It will help the rhizome to secure itself firmly in the soil and, at the same time, allow it to aptly sustain the subsequent flower stem without letting it fall down. It is a very bad idea to transplant the new iris rhizome divisions when they are dormant during the winter months, because the new plant will not be able to survive on the resources stored in the rhizome. Moreover, since the following growth period will only occur after the flowering season, transplanting the rhizome divisions during this period will most possibly give rise to flower stems that are shorter compared to the usual. In addition, the blooms too will be smaller. Dividing the existing iris clumps requires that you first excavate the entire plant with the help of a strong garden fork. Only retain the plumpest new rhizomes having new, vigorous, green leaf fans and an excellent root system. Make a clean cut to separate these types of rhizomes from the older plant. These rhizome parts should at least be of the size of a thumb. At the same time, cut back the leaves by roughly one-third of their original. Doing this not only helps to avoid wind-rock as well as loss of too much moisture, but also allow the new roots to get established sooner. Get rid of the older rhizomes that have become unproductive. These older rhizomes can be used for making composts.


If you are obtaining your irises from any nursery they will usually arrive by courier service or mail. The roots of these plants will be bare. Once you receive the plants, ensure that they have firm rhizomes. Also see if there are any dry leaves. Don't get concerned if you find the leaves of the new plants having a tendency to become dry and turn brownish. In fact, this is absolutely normal. What you need to check for is the strong roots of the plants. These roots may have been trimmed evenly at the nursery, but in any case they ought to be no less than 4 inches to 6 inches in length. While you are preparing your iris bed, allow the roots to be exposed to the air and place them in a place that is cool, dry and away from direct sunlight. While planting the rhizome, ensure that its top is at the same level with the soil's surface. When the bed has been prepared, make a planting hole in it, sufficiently wide to accommodate the young rhizome along with its extended roots. Place the rhizome in the middle of the opening on an elevated soil hump and spread its roots carefully downwards as well as horizontally. The roots should be placed deep enough to help the new plant to secure itself firmly in the ground. Remember, movement or wind-rock may prove to be the most harmful for the newly planted rhizomes of bearded irises, as this can rub off the roots the moment they emerge. After placing the rhizome, fill the gaps around it firmly with the soil dug up to make the hole. Use your feet to press the soil firmly, but be cautious not to harm the plant. Ensure that the rhizome is at the same level or a little higher than the normal soil level in your garden. After the planting is complete, water the plant liberally. Subsequently ensure that the soil is somewhat moist till the new roots appear or for roughly two weeks. After the new roots have emerged, they will allow the plant to endure arid period.


All through its growing season, the iris rhizome develops the length of the ground with its new roots and leaf fans in the growth end. The new leaves emerge from the middle of the fan, while the older leaves are thrust to the outer surface. Eventually, the older leaves turn brown, fall on the rhizome, almost covering its surface towards the ground. When the climatic conditions are extremely hot, these decomposing old leaves may possibly protect the rhizome from sunburn. However, you need to be careful, because in places where the climatic conditions are more of temperate nature, the decaying older leaves may also form a shelter and hiding place for snails, slugs, earwigs, slaters in addition to a variety of spores that results in fungal diseases. Therefore, it is prudent to inspect the plants from time to time, especially during the summer months, and get rid of the entire old foliage. Remember, the leaves of any plant are the source of the nutrients they require for growth. Therefore, it is advisable that you allow the plants to retain as much foliage as possible during their growing season. This will ensure that the plants will remain healthy and grow robustly throughout the ensuing season. At the same time, it is very important to ensure that the iris clumps are free from any invasion by weeds and also prevent other plants from overlapping the irises. It is not very difficult to keep the bearded irises clean and ensure their hygiene, provided you are familiar with their growth patterns. It is quite easy to remove relatively larger weeds having tap roots like dandelion or dock when you use a sharp spade. Only one deep angular thrust with the spade on the underside of the rhizomes (away from and avoiding the fans of the leaves) will be sufficient to slash the tap root of the invading weed. Placing your foot on the rhizomes firmly, pull out the weed. When you follow this method, the weed will come out effortlessly without disturbing the iris clump or causing any damage to it.

Irises Aril and Arilbred Irises Bearded Irises / Culture / Species Bulbous Irises Evansia or Crested Irises Japanese Irises Louisiana or Hexagona Irises Median Irises Miniature Dwarf Bearded Irises Novelty Bearded Irises Pacific Coast or California Irises Reticulata or Dwarf Bulbous Irises Scorpio or Juno Irises Siberian Irises Spuria Irises Tripetala Irises