Characteristics of the kentrantus plant, recommendations for planting and cultivation in a personal plot, advice on reproduction, problems with care and ways to solve them, curious notes, species and varieties.
Kentranthus or Centrantus can also be found under the name Red Valerian, but he has nothing to do with the medicinal "relative". The plant is included in the Valerianaceae subfamily introduced into the Caprifoliaceae family. The homeland of these representatives of the flora is considered to be the lands of southern Europe, namely the Mediterranean. The genus includes approximately twelve species, including some that have been introduced (introduced and successfully cultivated) by humans to other parts of the world, including Centranthus ruber in the western United States and Centranthus macrosiphon in Western Australia.
| Family name | Honeysuckle |
| Growing period | Perennial |
| Vegetation form | Herbaceous or bushy |
| Breeds | Seed or dividing the bush |
| Open ground transplant terms | Last week of May or early June |
| Landing scheme | Distance between seedlings up to 40-50 cm |
| Priming | Light, sandy, well-drained and fertile, medium (loamy) to heavy (clayey) soils, and even poor |
| Indicators of substrate acidity, pH | Any indicators, even very alkaline or acidic soils |
| Illumination level | Well lit place |
| Humidity level | Watering is carried out only during dry periods, does not tolerate waterlogging |
| Special care requirements | Top dressing is needed when planting in poor soil |
| Height and width options | Average 90 cm in height and up to 60 cm in diameter |
| Flowering period | June to September |
| Type of inflorescences or flowers | Semi-umbellate inflorescences |
| Color of flowers | Red, magenta, or pink |
| Fruit type | Seed capsule |
| The timing of fruit ripening | July to September |
| Decorative period | Summer |
| Use in landscape design | Decoration of flower beds and borders, in mixborders and rock gardens |
| USDA zone | 5 and higher |
The genus got its scientific name due to the combination of a pair of words in Greek "kentron" and "anthos", which translates as "spur" and "flower", respectively. So people noticed the structure of the flower, which includes a spur-like outgrowth, located at the base of the corolla.
All types of kentranthus have a shortened root system located close to the soil surface. These perennials have a herbaceous vegetative form, but can grow as dwarf shrubs. The stems rising above it are dense with good branching, which really resembles small bushes than grass. The color of the stems is greenish-gray, but towards the top it becomes paler. On average, the size of the stems can reach 0.9 m, while the growth of the curtain is measured in width about 0.6 m. Along the entire length of the shoots, leaf plates, painted in a dark green or bluish color, unfold. Only the lower leaves have small cuttings, the foliage at the top grows sessile. The shape of the leaves at the centrantus can be rounded and blunt at the top or takes on an elongated ovoid shape with an elongated or heart-shaped base and a pointed end. The surface of the leaves is smooth. The leaf plates are located opposite. Leaves can vary in length from 5 to 8 cm.
The stem is crowned with a peduncle characterized by branching. Moreover, each of the processes gives rise to small flowers. Semi-umbellate inflorescences are collected from the flowers. The petals in the flowers of the centranthus can take on a red or pinkish-purple hue, which is why the plant is often called "red valerian" or "red kentrantus". It is this species that is most loved by gardeners, and has undergone cultivation, which is why it is actively used in landscape design.
Flowering occurs twice during the growing season, while a strong pleasant aroma spreads around the plantings. The first wave of flowering falls on the period of June-July, and for the second time it will be possible to enjoy the flowers of the centranthus in August-September. These plants are hermaphrodites (have male and female flowers). Pollination of inflorescences occurs with the help of bees or lepidoptera insects (butterflies).
Also, centrantus seeds will be formed twice (from July to September), which are collected in seed pods. When the seed material is fully ripe, it opens easily and the seeds spill out, which promotes self-sowing.
The plant is bright and looks great in any part of the garden, but at the same time caring for it is simple, you just have to follow a few rules.
Recommendations for planting and caring for kentranthus in the open field
- Landing place red valerian should be well lit, as this will be the key to subsequent lush flowering. It will be able to put up with partial shade, but it does not tolerate a thick shadow. It is also noted that even direct midday sunlight does not harm the deciduous mass of the plant. However, at the same time, the centrantus will not be able to develop normally under the influence of drafts; warmth and protection from cold and wind should be provided at the landing site. You should not place such bushes in damp places, near the occurrence of groundwater, as this will negatively affect the state of the root system. Plants have been observed to withstand marine exposure.
- Soil for kentrantus choosing will not present problems, since this representative of the flora is suitable for light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained substrates and can grow on nutriently poor soil mixtures. Suitable soil pH: acidic, neutral and basic (alkaline) compounds and can thrive in very alkaline soils.
- Planting centrantus when grown in open ground, it should be carried out in the last week of May or with the arrival of summer, since during this period there is no need to fear that the seedlings will be damaged by recurrent frosts. The pit for planting is prepared in such a way that the root system of the centrantus fits into it, and a finger-sized space remains between the walls and the plant. At the bottom, it is recommended to lay a layer of 3-5 cm of drainage material, which is taken as small expanded clay, pebbles or pieces of broken brick. A soil mixture of such a volume is poured on top so that it covers the drainage and only then a red valerian seedling is placed in the hole. Soil is poured along the edges and slightly compacted, and then the substrate is moistened abundantly.
- Watering, despite the moisture-loving nature of the kentrantus, it is recommended to carry out only when the weather is dry and hot, but in the usual case the plant does not like waterlogging of the soil and natural precipitation is enough for it.
- Fertilizers when growing centrantus in the open field, there is no need to make it if the planting was carried out in a nutritious soil mixture. Otherwise, it is best to apply top dressing every 14 days. During the period of activation of vegetative activity, fertilizers should have more nitrogen in the composition (for example, nitroammofosk), then nitrogen-free preparations, such as borofosk, are also suitable. To stimulate flowering, it is necessary to use phosphorus and potassium preparations, such as Ecoplant or Potassium Monophosphate.
- General tips for caring for centranthus. In order to achieve re-flowering, when the first wave comes to an end, it is recommended to cut all inflorescences to the upper leaf plate. This will stimulate the formation of new flower buds. After shearing, the plant quickly regains its former appearance. With the arrival of autumn, all stems must be cut off completely. Since the aging of the kentrantus is quite rapid, every 3-4 years it will be necessary to replace the old plantings with young, grown seedlings poured with new branches. If this rule is not adhered to, then the number of flowers on the bush from year to year will begin to decrease, some of the branches at the base become lignified and lose their leaves. Since the plant is famous for the peculiarity of self-seeding, pruning and thinning of plantings from young shoots should be periodically carried out. If you do not adhere to this rule, then after a couple of years the red valerian bush begins to "crawl out" beyond the territory allotted for it.
- Wintering kentranthus directly depends on the climatic conditions of the area where the cultivation is carried out. If the region has mild winters, then the place where the red valerian bushes grow, after cutting the stems, is simply covered with a layer of dry leaves, you can use peat or humus. When winters in the growing area are severe or snow-free winters are expected, then a more serious shelter must be built. So dry rags and non-woven material (for example, lutrasil) are suitable, which is recommended to be fixed with bricks in the corners. Or above the plantings of the centrantus, a frame structure is installed, on which an agrofiber shelter is then thrown.
- Seed collection kentranthus is carried out for future sowing, so that you can then decorate the flower bed by filling the voids with new plants. The formation of seed pods begins from the second year of the growing season, while their unharmed ripening is noted - over the course of a month to one and a half. Collect the boxes as they ripen. To do this, the stem with the fruits of the centranthus must be cut off and put in the shade for several days so that the bolls can ripen. Then the seeds are removed from them and stored in a dry and cool place, not allowing them to become damp. When stored indoors, red valerian seeds are best kept away from batteries or heating appliances. Seed material is recommended to be poured into paper envelopes, glass containers or tin boxes. Pouches made of fabric, plastic bags with a sealed fastener may be suitable.
- Application of centrantus in landscape design. Since there are plants with different stem heights in the genus, with the help of them you can plant mixborders and rock gardens, filling the voids between the stones with such bushes. Plantings of red valerian can be used to decorate rabatki, garden paths and form borders. If there are dry slopes or gazebos on the site, then the centrantus bushes will become their real spectacular decoration. Also, undersized species can be used as a ground cover crop. It is not uncommon to plant seeds on stone walls and in paving, where red valerian bushes will subsequently create a delightful casual, natural effect. The stone backdrop gives them the perfect setting. These plants are generally long-lived and grow especially well in marine areas, where they are a common feature of hedges and walls. Adonis or other perennials, like semi-shrub oak sage, gypsophila or carnations, are the best neighbors for centrantus.
See also tips for growing honeysuckle.
Tips for breeding centrantus
To grow new plants of red valerian, it is recommended to use the seed or vegetative method, the latter being the division of an overgrown bush or rooting of cuttings.
Reproduction of kentrantus using seeds
Seed material can be sown in greenhouse conditions or directly to a flower bed in open ground. In the latter case, sowing is recommended in the fall, so that the seeds undergo natural stratification, and immediately on the permanent growth of centrantus bushes. Before the onset of cold weather, locations with crops must be provided with a shelter, which can be peat chips, a layer of dry foliage or other mulching material. However, sowing in open ground can also be carried out in the spring, when the soil warms up (in April or May). But in this case, young seedlings may lag behind in development, and the flowering will not be so abundant and long.
It is best to sow kentranthus seeds in the spring in do-it-yourself or specialized greenhouses. The recommended time for such sowing is the end of winter or the first week of March. If it is decided to build a greenhouse yourself, then a container or pot is used for this, with loose and nutritious soil (you can take a peat-sandy one) and cover such a container with a transparent plastic wrap or put a piece of glass on top. In addition, crops should be placed in a warm, well-lit place, for example, on the sill of the south window. But in this case, when seedlings of kentranthus appear, it will be necessary to draw a light curtain on the window at lunchtime so that direct sunlight does not burn young shoots.
When caring for crops, it is necessary to ventilate daily, removing the shelter for 10-15 minutes. As soon as the first shoots appear, such ventilation is lengthened, and after 14–20 days, the film or glass is completely removed. As the seedlings of kentrantus grow up, they become cramped in the planting container and it is recommended to perform a dive. To do this, plants are transplanted in separate pots or in similar containers, leaving large distances between seedlings of about 10-15 cm. It is best to dive into pots made of pressed peat, which will greatly simplify transplanting to a flower bed. Only with the arrival of summer, the centrantus seedlings are ready for transplanting into open ground.
It happens that numerous shoots appear next to the red valerian bush, due to self-seeding. Therefore, in the spring, as such plants strengthen and grow, they can be transplanted to a new location, leaving 40-50 cm between seedlings.
Reproduction of centrantus by division
This process is best done in an early vein (when growth has not yet begun to activate) or in autumn days (after flowering is complete). If the age of the bush approaches a three-year period, then you should think about rejuvenating it by dividing it. The bush is stitched around the perimeter and, with the help of a sharpened shovel, a part of its root system is cut off, with a small number of stems extending from it. The diaper should not be made too small, as this will complicate the process of its engraftment. After that, with a garden pitchfork, the cut off part of the centrantus bush is removed from the ground and it is immediately planted in a new, pre-prepared place according to the rules of primary planting.
Reproduction of kentrantus by cuttings
For this operation, you need to choose the time from the middle of summer or in August. For cutting blanks, strong branches are chosen, the length of which should be at least 15 cm. After that, the cuttings are planted on the prepared breast, deepening by about 10 cm. Caring for such cuttings will include timely watering as the soil surface dries and weeding from weeds … When the buds begin to swell on the seedlings and the leaves bloom, this is a sure signal that rooting is complete and the plants are ready for transplantation to a permanent place of growth in the garden.
Problems arising in the care of centrantus and ways to solve them
Although the plant is highly resistant to diseases affecting garden plantings, it can suffer from violations of planting rules, such as, for example:
- lack or poor quality drainage layer;
- abundant watering, provoking waterlogging of the soil and, as a result, decay of the root system of the kentranthus.
If the soil has undergone acidification, then dark spots formed on the sheet plates will be a sign of the problem. For a solution, it is recommended to remove all affected parts of the bush and treat it with fungicidal preparations, among which Fundazole or Bordeaux liquid is the most popular. Also, during the cultivation process, you need to ensure that the plantings of red valerian are not too thickened, for this it is necessary to carry out periodic thinning.
Also, the plant does not tolerate temperature changes, which is explained by the lack of frost resistance and naturally affects the rare appearance of centranthus in the gardens of our latitudes. At the same time, it is noted that the plant is not susceptible to attacks and harmful insects, diseases of viral and infectious origin.
Read also about possible diseases and pests when cultivating a snowberry
Curious notes about centrantus
Mostly among centranthus, the red species is popular - Centranthus ruber. Its young leaf plates are usually used in cooking, both fresh and cooked. It is introduced both in salads and in the form of a vegetable crop. However, you need to remember about the bitter taste of the deciduous mass. The rhizome is used in soups.
It often happens that the common people confuse this species with medicinal valerian (Valeriana officinalis), since it has a very strong effect on the nervous system, but this representative of the flora does not have known medicinal properties. According to some reports, centrantus seeds were used in ancient embalming.
Types and varieties of kentrantus
Kentranthus red (Centranthus ruber)
specific name Kentrantus Ruber or Red Valerian, also in various countries you can hear the following nicknames - valerian spur, kiss me, fox, devil's beard and Jupiter's beard. In nature, this species is native to the Mediterranean and has been introduced in many other parts of the world as a horticultural crop. Naturalized in France, Australia, Great Britain, Ireland and the USA. In the United States, it can be found wild in western states such as Arizona, Utah, California, Hawaii, and Oregon, usually in rocky terrain below 200 meters. Such plants are often found on roadsides or urban wastelands. The species can tolerate very alkaline soil conditions as it tolerates lime well and is often seen on old walls in Italy, southern France and southwest England.
Kentrantus rubra is a perennial growing in the form of a shrub, although, depending on the growing conditions, it can take a form from grass to bush, and then its stems have a lignified base. The height of the stems can approach 1 m, while the width of the bush is measured at 0, 6 m. The foliage of the red centrantus varies in the range of 5–8 cm. Their outlines from the base to the top of the stems can change, since in the lower part they have petioles, and at the top they grow sedentary. The leaf plates are arranged in pairs opposite to each other. Their shape is oval or lanceolate.
With abundant flowering, small flowers are formed in kentranthus rubra (the diameter when opening is only 2 cm). The buds are collected in dome-shaped or semi-umbellate showy inflorescences of large sizes. Moreover, these inflorescences are composed of rounded clusters containing flowers. Each of the flowers has five petals and a spur. The color of the petals in them most often takes on a red brick or crimson-red color scheme, but shades can be dark red, pale pink or lavender.
There are the most popular varieties of red centranthus:
- Alibus or Albiflorus (Albiflorus), the number of such plants accounts for about 10% of the total number of plantings. This variety is characterized by snow-white flower petals. It blooms in June, and in regions with a cool climate begins randomly throughout the summer and even in autumn.
- Coxineus is a long-flowering variety. It has a bushy shape. Strongly branched stems reach a height of 0.8 m. They are covered with bluish leaves. When blooming, a strong aroma is carried. It is often used as a food plant by the larvae of some species of Lepidoptera. Since the flowers have a bright pink color, it is called "crimson ringing". The diameter of the flowers is only 1 cm. The inflorescences take on a pyramidal shape. Pollination occurs by bees and butterflies. The seeds are somewhat similar to the bunches formed by dandelions, which allows them to spread with the help of the wind.
- Rosenrot inflorescences are characterized by a purple-pink color.
Centranthus longiflorus
is of Turkish origin, can be found in the Transcaucasus, in the middle mountain zone. Herbaceous perennial plant with a large number of stems forming. Their height reaches 30–70 cm, and in some specimens even one meter. The stems grow straight, thick, with a bare surface and a bluish bloom. Numerous leaves grow on them; branching is often present in the middle part. In this case, the twigs are shortened and rather thin.
Leaf plates of long-flowered kentranthus reach a length of 8 cm. Their shape varies from broadly to narrow-lanceolate. In the twigs, the leaves take on a linear outline with a blunt top. At the same time, such foliage is sessile, whole-edged with a bare surface, which is covered with a bluish bloom. During flowering, the formation of inflorescences does not exceed the length of 20-30 cm. They crown the tops of the shoots. The shape of the inflorescences is most often corymbose-paniculate.
The size of flowers of long-flowered centranthus with a spur reaches a length of 1, 2–2 cm, which exceeds the parameters of flowers of other species. The corolla tubule is narrowed, cylindrical. There is a funnel-shaped expansion in the upper part. The rim has five lobes of unequal size. The length of a straight spur does not go beyond 0.6–1 cm. Its shape is rather narrow. The color of the petals in the flowers is red-purple. Flowering occurs in the period May-July. As a culture, the species began to grow in 1759.
Narrow-leaved Kentranthus (Centranthus angustifolius)
A native of the western mountainous regions of the Mediterranean up to an altitude of 2400 m. It is more difficult to meet than the red centranthus species. The name accurately reflects the size of sheet plates of this type, their length varies in the range of 8-15 mm, with a width of about 2-5 mm. The tip of the leaves is pointed. The flowering process stretches from May to July. Its characteristics are so similar to the Centranthus ruber that some experts combine it into one species.
Kentranthus valerian (Centranthus calcitrapa)
may occur under the name Spanish valerian. Annual, has the smallest size of the entire genus. The height of its stems does not go beyond 10–40 cm. The stems grow bare, bluish-green in color. The leaves are arranged opposite and in pairs. In the lower part, they are petioled, spatulate, with a blunt apex, incised from the sides or with a jagged edge. Their length is 10 cm. In the upper part, the leaf plates are sessile, they can grow pinnate.
This species begins to bloom earlier than others, and falls in the period from mid-spring to the end of June. Inflorescences are located at the tops of the peduncles or in the upper part of the stems, originating from the nodes of the leaf plates. Flowers in inflorescences take on a reddish-ash or pinkish hue. The rim tube reaches 2 mm in length. The spur is shortened. The flower has five leaves and a single stamen.
Kentranthus macrosiphon,
also commonly referred to as long spur valerian. This species is native to North Africa and southwestern Europe, but has naturalized in many areas, including southwestern Western Australia. An annual herb, the stems of which are usually growing to a height of 0.1 to 0.4 meters. It blooms in spring and early summer, inflorescences are formed by pink-red-white flowers.
Centranthus trinervis
is endemic to Corsica, France, where there is a single subpopulation of only 140 individual plants. The common name of the plant in French is Centranthe A Trois Nervures. Its natural habitat is shrub vegetation of the Mediterranean type. It is currently threatened by the loss of its habitat. It is considered by the IUCN as one of the 50 most endangered species in the Mediterranean region. The inflorescences, crowning the flowering stem, are composed of pale pink flowers.
Related article: Planting, care and reproduction of weigela in open ground
Video about growing kentranthus in open ground:
