How and when irises bloom: timing, period and features of flowering

Perennial irises are frequent guests in flower beds. You can meet them in gardens, parks and squares; these plants are used by landscape designers and ordinary amateur flower growers who like the variety of species, varieties and colors. There are few reasons why irises do not bloom. These perennials are unpretentious and undemanding to care for, so their lack of flowering is a rarity, however, sometimes it happens.

Features of flowering irises

There are a huge number of irises - several tens of thousands of different varieties and hybrids. They differ among themselves, including in terms of flowering. Iris also have features in the structure of the flower itself. The tubular perianth consists of 6 petals fused at the base. In this case, 3 of them are bent down, and 3 others are raised up. In the special literature, these types of petals have their own name - fouls and standards.

Flowers differ from other species in a special structure.

Depending on the shade of irises, several groups are still subdivided, into which species with characteristic signs of coloring are combined: one or two colors, the nature of the coloring, its intensity.

The shape of the arrangement of the petals can also be different, depending on this, the following classification is adopted:

  1. Classic.

    Classic flower shape - downward fouls

  2. Semi-floating.

    In a semi-floating flower, the fouls are at an angle

  3. Soaring.

    Fouls of the floating flower are directed horizontally

Important! In some varieties of Japanese irises, the standards may lie in the same horizontal plane as the fouls. Therefore, for them, in the classification, the hovering and semi-steaming form are divided into 2 types, with 3 and 6 petals, respectively.

The petals of Japanese species have a "floating" shape

The perianth lobes themselves are also subdivided into 3 types, depending on the edge of the petal:

  1. Straight or austere style.

    Flowers of a strict style have an even edge of the petals

  2. Corrugated.

    Shirred types have a wavy edge on the petals

  3. Lacy, or bubbly - the petal plate has delicate curls, the edge looks foamed.

    Lace types are especially decorative

In addition, there are 2 large groups of irises:

  • bearded;

    The stripe of villi on the petals is a hallmark of the bearded species.

  • beardless.

    There are no villi on the flower of beardless subspecies

The former got their name for the presence of a characteristic path of hairs on the outer lobes of the perianth, in the latter it is absent.

When irises bloom, in what month

Ultra-early varieties of irises (according to the international classification have the designation VE) bloom at the end of April. These are short, dwarf and miniature species. Then, in May-June, the buds appear on the larger border varieties. The latest, tall, VL-classified irises bloom in July.

Important! Some iris varieties are classified as "re-bloom", which includes species that, under certain conditions, can bloom again in autumn, in September-October.

How long do irises bloom

The flowering period of irises depends on many factors, including natural (climate, weather conditions) and artificial (planting site, soil characteristics, care). Under normal conditions, flowering lasts 10-14 days.

List of reasons why iris does not bloom, and what to do

If the iris does not bloom in due time, you should definitely pay attention to this. There may be several reasons for the absence of buds. They are associated with planting and leaving, as well as with some natural causes beyond human control.

Wrong variety selected

The wrong choice of iris varieties for planting may well affect their flowering. To prevent this from happening, you should definitely purchase zoned varieties, as well as those that are suitable for the specific conditions of the site. For example, moisture-loving marsh or Siberian irises should be planted next to water; dwarf bearded species should be chosen for alpine slides.


Often the reason for the lack of flowering in irises is the weather. This is especially true in areas with an unfavorable climate. Iris does not bloom well after a cold, rainy spring, due to recurrent frosts.

Too damp and cold weather can cause irises to lack flowers.

In some cases, prolonged rains or, conversely, severe drought can lead to the fact that the plants do not have enough strength to fully form the buds. Due to the abundance of moisture, the roots may suffer, due to their decay, the nutrition of the aboveground part of irises is disturbed. The same can happen with water shortages, especially during the budding period.

Violation of landing rules

Inappropriate site selection or iris planting irregularities are the most common reasons why these plants lack flowers. It must be remembered that for planting these perennials, you need to choose sunny, wind-protected places with loose, well-drained soil. If, for example, a flower bed after construction on the site falls into the shade, then due to a lack of lighting, the flowering will significantly weaken, and in some cases it may not be expected at all. If the problem, why irises do not bloom, is only in this, then it is solved by transplanting plants to a more suitable place.

Correct planting is the key to the future flowering of irises

Another reason why iris does not bloom is the excessive deepening of the rhizomes when planting or transplanting. When carrying out such work, they should be located almost on the surface, so that the growth buds, together with the upper root comb, are above the ground level. If the rhizomes are very deep, then they should be partially torn apart, exposing the top of the root.

Violation of the rules of care

Although irises are unpretentious, some care is still required for them. If you plant flowers and then leave them to their fate, they may not bloom.

Irregularities in watering schedule

Most irises do not like excessive soil moisture and negatively perceive excess moisture, with the exception of certain species. Too frequent and abundant watering will contribute to the development of root rot, and this can lead not only to a lack of flowers, but also to the death of the plant itself. Irises are more tolerant of hot weather, but at this time they need watering, especially when the plants are in the bud formation phase and during flowering periods.

Lack of food

Irises grow quite quickly, while absorbing a lot of nutrients from the ground. If you do not apply additional fertilizers, the soil fertility will very soon decrease to such an extent that the plant will not be able to "feed" the buds that are forming and will begin to shed them.

Irises need periodic feeding

To prevent this from happening, irises are fed several times during the season with complex potassium-phosphorus fertilizers, and in the spring - also with nitrogen fertilizers, if there is a growth deficit. However, nitrogen fertilization should be used with caution. An overabundance of it can lead to the fact that the irises will not bloom, the plants will have only leaves.

Lack of shelter in winter

Not all varieties and types of irises are well tolerated by the harsh Russian winters. Only a small part of them can hibernate without shelter. In order for the plants to survive the winter, they are covered with non-woven material, covered with dry leaves and spruce branches, houses are made of slate or roofing material, which are subsequently covered with snow. If this is not done, then the flower buds of most types of irises can freeze and die, this will lead to the plant growing, but it will not have buds.

The need for a transplant

The reason why irises do not bloom may be due to their high stocking density. Over time, these perennials grow strongly, their rhizomes increase significantly in size and literally grow on top of each other. A lot of competition forces the plants to spend all their energy only on the growth of greenery; in this case, flowering cannot be expected.

About 1 time in 4 years, the rhizomes of irises are divided and planted

To avoid such a situation, about once every 4 years, irises are dug out of the ground, the rhizomes are divided into parts and planted.

Pests and diseases

In unfavorable conditions, various fungal diseases begin to develop especially quickly, which can cause not only the absence of flowers, but also the death of the plant. Weakened irises become prey for insect pests, the presence of which also negatively affects flowering. To protect flowers from diseases, plantings are periodically treated with fungicides, for example, Bordeaux liquid. Insect pests are fought with insecticides, processing flowers in accordance with the instructions for the preparation used.

Fungal diseases can kill the entire plant

Important! The best remedy against diseases and pests is prevention: timely harvesting of plant residues, weeding, loosening of the soil, adherence to the irrigation schedule, as well as the selection of high-quality planting material.

How to make irises bloom

To make irises bloom, you need to clearly find out the reason why this did not happen. First of all, you need to check the location of the beds and the deepening of the rhizomes, sometimes it is enough to dig them out a little in order to get abundant flowering next year. It will not be superfluous to clarify whether the variety is suitable for growing in a particular region, you may have to completely update the planting material.

To find the best place for the irises, you can arrange several flower beds in different parts of the garden.

It is advisable to empirically determine the best location, the optimal composition of the soil, and try out various care options. If you take it seriously, then, as a rule, the cause of weak flowering or its complete absence can be quickly found and eliminated.


There are not so many reasons why irises do not bloom. If you follow all the recommendations for growing these perennials, then you may not face such a situation at all. If the flowering of irises is absent for a long period, then you need to seriously deal with this, analyze the reasons and draw appropriate conclusions.

Watch the video: Iris Care After Flowering (June 2021).