The iris or iris enchants the viewer with its beautiful flowers that shine in a wide variety of colors of the rainbow. The genus is extremely rich in species and varieties, with the right variety for every location. Whether shady and moist ground or dry ground and sun: the gardener has the choice. Most species are hardy and also pleasingly uncomplicated to care for.
What distinguishes irises in the garden?
Irises, also known as irises, are magical flowers that come in many different colors and growth forms. They are easy to care for, hardy and suitable for any location, both shady, damp areas and dry, sunny places in the garden.
Origin and distribution
Irises are only native to the northern hemisphere of the earth and almost exclusively in temperate climate zones - but the magnificently blooming summer flowers are found in an unmanageable variety on almost every northern continent. The generic name “Iris” refers to the Greek goddess of the rainbow of the same name, as irises are also available in an incredible variety of colors. The spectrum of different flower and growth forms is just as inexhaustible, as there are a wide variety of variations, from the low-growing dwarf forms to the tall-growing bearded irises. No wonder then that the Association of German Perennial Gardeners named the popular plant “Perennial of the Year” in 2016.
Usage
The possible uses for irises depend largely on the type and variety chosen. Varieties for moist substrates feel at home on the edge of a garden pond or a stream, while iris species adapted to dry and sunny locations fit wonderfully into the perennial bed or rock garden. You can also cultivate the magnificent perennials wonderfully in pots, as long as there is an adequate supply of water and nutrients. The dwarf forms in particular - such as short bearded irises - are suitable for container cultivation.
In the bed, the pretty flowers with the unusual blooms are often combined with perennials and bulbs such as peonies (Paeonia), delphiniums (Delphinium), daylilies (Hemerocallis), poppies (Papaver), tulips (Tulipa) and lavender (Lavandula) and combined with grasses such as blue fescue (Festuca cinerea) or giant feather grass (Celtica gigantea).
Appearance and growth
With the exception of the reticulated iris, all iris species form rhizomes or tubers, not bulbs such as daffodils or crocuses. In spring, the long, sword-like leaves and flower shafts, which are between 15 and 120 centimeters high, depending on the species and variety, emerge from these survival organs. After the capsule fruits have formed and ripened in late summer or autumn, all above-ground parts of the plant die and only the rhizome or tuber overwinters. Irises are herbaceous, perennial plants.
Flowers and flowering time
The beauty of irises is primarily due to their unusually structured flowers that shine in many different colors. A characteristic feature of iris flowers is that they are divided into three parts: each consists of three upright standards and three additional bracts that hang downwards. These can be the same color or different colors. In some varieties, the bracts are also fringed or ruffled at the edges, and the various bearded irises also have a hairy “beard” on the back of the flower. The pistil, which consists of a three-branched style and the anthers, sits between the cathedral leaves and the bracts.
Toxicity
Parents have probably heard of violet root as a teething aid for babies or even offered it to their child. However, contrary to all assumptions, the root, which has been used for centuries, does not come from the blue violet, but from the iris or iris. The native yellow iris, also known as the swamp iris, is also used as a wound healing agent in homeopathy.
However, such traditional applications in folk medicine should be treated with caution: All iris species are poisonous and can cause typical symptoms of poisoning such as vomiting, diarrhea, nausea, etc.cause. In addition, after consuming the spicy substances it contains, irritation of the mucous membranes, increased salivation and difficulty swallowing occur. This applies not only to humans, but also to domestic and farm animals such as cattle, sheep, goats, horses, dogs and small rodents.
Location and soil
The ideal location for irises depends on the specific species. Typical marsh plants such as the Siberian iris (Iris sibirica, also known as the meadow iris) or the native yellow iris (Iris pseudacorus) fresh to wet places in the garden, for example in a damp meadow or directly at the edge of the pond.
Other irises, on the other hand, require a rather dry location with nutrient-rich, clay-rich and well-ventilated soil and lots of sunlight. In contrast to the swamp iris, these species do not tolerate permanent moisture and are therefore best placed in a perennial bed or even in a rock garden. The popular bearded irises, for example, are quite drought tolerant and therefore harmonize very well with corresponding species such as sedum or thyme.
Furthermore, the small species in particular can be cultivated very well in pots, as long as you protect the planters from excess moisture - especially during the winter.
Planting irises correctly
The ideal planting time for all types of irises is the months between the end of July and the beginning of October, although if the weather permits you can also sink the rhizomes into the ground in March or November.
When planting the rhizomes, make sure that they are placed flat in the planting pit and that the top third still protrudes from the ground. Before planting, loosen the soil thoroughly and add compost and, if necessary, sand to the excavation. For improved drainage in the case of heavy, clayey substrates, fill a layer of sand about the thickness of your thumb into the shallow planting pit and place the rhizomes on top.
For large-scale planting, for example for a border, you should plan between 12 and 16 low-growing irises and between five and seven tall-growing species per square meter.
Watering irises
Planted and well-rooted irises basically only need additional watering if the drought persists. Specimens grown in pots, on the other hand, must be watered regularly, but must not be left wet - good drainage is therefore essential, and a thumb test must be carried out before each watering.
Fertilize irises properly
Irises in the garden simply need to be fertilized with compost and a handful of horn shavings in March or April, which can be repeated again in June if necessary (e.g. if deficiency symptoms occur). Alternatively or for potted plants, use a potassium-based fertilizer (€43.00 on Amazon).
Cut irises correctly
Cut off the wilted flowers about ten centimeters above the ground to prevent seeds from forming. Some irises can be persuaded to bloom a second time in this way. In turn, you only remove the leaves in autumn when they have withered and can be easily pulled off. Under no circumstances should you take this step earlier, as the underground rhizomes or tubers extract valuable nutrients from the foliage and store them for the next shoot.
Propagate irises
Every three to four years you should dig up the large-flowered species in late summer and divide the rhizomes. In this way, you not only multiply the irises, but also rejuvenate the otherwise aging plants and thus ensure increased flower development. Cut the rhizomes at the constricted sections; each section should have roots and a tuft of leaves. Shorten the leaves by about half so that the plants do not lose unnecessary moisture until they take root.
Wintering
Irises are generally hardy, so the tubers or rhizomes can remain in the ground during the winter months. The Siberian iris and other species suitable for moist soils also receive a cover made of straw and leaves. Irises grown in pots can also overwinter outside, but should be placed in the rain shade or under a canopy.
Tip
Provide good snail protection around your iris plantings, as they eat the juicy leaves within a very short time. Voles, in turn, taste the nutritious rhizomes or tubers.
Species and varieties
The group of irises (bot. Iris) is huge: 285 wild species alone are known, all of which mostly come from the temperate climate zones of the northern hemisphere. There is also an almost unmanageable number of natural hybrids and cultivated forms, of which the so-called bearded iris is probably the best known. However, this is not a specific species, but a group of iris cultivars with a characteristic feature: their flowers not only bloom in all the colors of the rainbow, but also have a small beard.
Popular cultural forms
While botanists divide the genus into six different subgroups, gardeners only distinguish between bulbous and rhizome irises. The last group includes the already mentioned bearded irises, which in turn are sorted into three further subgroups:
- Dwarf irises (Iris barbata 'Nana' hybrids): maximum 30 centimeters high, flowering from mid-April
- Medium-tall bearded irises (Iris barbata 'Media' hybrids): growth height up to 70 centimeters, flowering period from the end of April / beginning of May
- Tall bearded irises (Iris barbata 'Elatior' hybrids): growth height more than 70 centimeters, flowering from the end of May
Interesting varieties for the garden include these:
- 'Calling Cadence': two-tone yellow and burgundy flowers, height approx. 90 centimeters
- 'Christmas Eve': two-tone white and yellow flowers, height approx. 95 centimeters
- 'Cracklin Rosie': burgundy red flowers, height approx. 100 centimeters
- 'Crooked Little Smile': two-tone yellow and blue flowers, height approx. 80 centimeters
- 'Embrace Me': pink flowers, growth height up to approx. 100 centimeters
- 'Joyful Journey': flowers in orange and yellow, growth height up to approx. 90 centimeters
- 'Misty Morning Melody': two-tone blue and white flowers, height approx. 95 centimeters
- 'Shelter from the Storm': two-tone blue and light blue flowers, height approx. 100 centimeters
Other hybrid species
Over the centuries, various hybrid species and varieties have developed naturally, which are also often planted in the home garden:
- Bristled iris (Iris setosa)
- Great iris (Iris magnifica)
- Bare-stem iris (Iris aphylla)
- Reticulated Iris (Iris reticulata)
- Rainbow iris (Iris innominata)
- Butterfly Iris (Iris orientalis)
- Terracotta iris (Iris fulva)
Wild species for the garden
The gardener also makes a distinction between irises for moist locations and irises for rather dry locations. These uncomplicated species are ideal for swamp beds or the edge of the pond:
- Swamp iris (Iris pseudacorus): native species
- Siberian iris (Iris sibirica): also meadow iris
- Japanese iris (Iris ensata)
- Japanese iris (Iris haematophylla)
The following species, however, prefer a dry and sunny place in the garden:
- Steppe iris (Iris spuria)
- Bastard iris (Iris Spuria hybrids)
- Grass iris (Iris graminea)
- Colorful iris (Iris variegata)
