Acanthus plants develop characteristic leaves, the shape of which has been used as a model for ornaments in the decorative arts. The perennials enchant various themed gardens. Anyone who takes a closer look at their requirements will enjoy the breathtaking splendor of flowers for many years.

Prickly Bear Claw is a pretty ornamental plant

Table of Contents

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  1. origin
  2. growth
  3. leaves
  4. blossom
  5. heyday
  6. fruit
  7. use
  8. Is Acanthus Poisonous?
  9. Which location is suitable?
  10. What soil does the plant need?
  11. The right planting distance
  12. Propagating Acanthus
  13. sowing
  14. Acanthus in the pot
  15. balcony
  16. Pour acanthus
  17. Fertilize acanthus properly
  18. Properly cut acanthus
  19. How do I plant correctly?
  20. hardy
  21. fungus
  22. Acanthus does not bloom
  23. sorts

    24. origin

    Acanthus is a genus of plants that belongs to the Acanthus family. It comprises 20 to 30 species whose main area of distribution is in tropical and subtropical climate regions. A few representatives are native to the Mediterranean region and Asia. The species are also referred to as Bärenklau. But the plants have nothing in common with the genus Heracleum of the same name.

    There are four types of ornamental plants:

    • Hungarian or Balkan Hogweed (Acanthus hungaricus)
    • Spiny Hogweed (Acanthus spinosus)
    • True or magnificent hogweed (Acanthus mollis)
    • Syrian Hogweed (Acanthus syriacus)

    growth

    The plants are perennial and mostly herbaceous. A few Acanthus species grow as semi-woody shrubs. They often develop underground rhizomes, which serve to survive and vegetatively reproduce. With the help of the runners, the plants form dense stands. The shoot axis grows prostrate or upright. The growth heights of the individual species are very different. They are between 30 and 150 centimeters.

    leaves

    The acanthus family mostly develop opposite leaves. A few species have whorled or basal leaves that are clustered. In all species they are divided into stem and blade. The leaves can have a simple structure. All four ornamental plants develop deeply dissected, pinnate leaves with a smooth or toothed to thorny leaf margin. They are reminiscent of oversized dandelion leaves and are referred to as ornamental because of their distinctive shape.

    blossom

    At flowering, Acanthus species become real eye-catchers, because their spike-like inflorescences are covered with hood-shaped individual flowers. Her four petals are fused into a partially reduced upper lip and an enlarged lower lip ending in three blunt petal lobes. The flowers grow up to five centimeters long and are carried by two bracts that are armed with thorns. They enclose the flower like a collar. The inflorescence reaches heights between 40 and 200 centimeters.

    heyday

    The flowers appear between June and August. They are whitish in color and often develop pink nuances. Some species have bright pink-tinged petals. Among the wild forms there are yellow, scarlet or blue flowering species.

    fruit

    In autumn, numerous capsule fruits develop on the inflorescences, which contain between two and four seeds. When the fruit ripens, the capsules burst explosively along pre-formed seams, so that the seeds are thrown out.

    use

    The plants are suitable for the design of colored perennial beds. Large species come into their own in a single or pair position. Lower ornamental plants harmonize in small groups. Acanthus perennials fit perfectly into the natural garden because of their wild shape. Because of the ornamentally shaped leaves, the plants harmonize with stone walls, water basins or next to stone steps on terrace slopes. Since the parent species of the ornamental plants come from the Mediterranean region, they are suitable for designing Mediterranean gardens. They set color accents in stone structures.

    These plants go well with Acanthus:

    • Catnip (Nepeta)
    • Yarrow (Achillea)
    • iris
    • Sea kale (Crambe)
    • Stuffed Gypsophila (Gypsophila paniculata)

    Is Acanthus Poisonous?

    Acanthus species are not poisonous and can be planted in the garden without hesitation. Many species are used in natural medicine. They relieve coughs and help with respiratory diseases, flu and colds. Externally, extracts of the plant parts are used for gout, sprains or bruises. Ointments promote the healing of burns and wounds.

    Which location is suitable?

    The species from the Mediterranean region prefer locations on scree and in stony terrain. Plants from tropical regions need wetter locations. All ornamental plants thrive in sunny locations. They tolerate partially shaded locations.

    What soil does the plant need?

    Cultivated Acanthus species thrive on a well-drained substrate with nutrient-rich and profound properties. They like a fresh soil. They don't have any problems with short droughts. Slightly loamy soil that can retain moisture is ideal. If the water accumulates in the substrate, the roots will rot quickly.

    The right planting distance

    Before planting, note that the perennials can reach considerable proportions. Low-growing companion plants are quickly crowded out. Place Acanthus in the bed at a planting distance of at least 70 centimeters from neighboring plants. There should be no more than two specimens per square meter.

    Propagating Acanthus

    In the spring you can multiply Bärenklau by division. Divide the excavated rhizome into several pieces so that each root piece has enough fine roots and shoots.

    Acanthus species can also be propagated via root cuttings. In autumn, cut a rhizome into pieces about three inches long and stick the cuttings in a mixture of sand and peat. The substrate is covered with a two centimeter thick layer of soil and moistened. Store the jar in a cool place. As soon as the first sprouts appear, the pot is placed in a light location.

    sowing

    Immediately after flowering, you can harvest the unripe capsules and store them in a sealed container. Here the seeds continue to ripen until the fruit bursts open. The seeds are spread on potting soil between November and March and lightly covered with soil. The seeds of the Acanthus species are dark germs.

    The substrate should be kept slightly moist for the next two to four weeks. Place the planter in a bright place with temperatures between 18 and 22 degrees Celsius. After this phase, the seeds need a cold stimulus that stimulates germination. The pot is placed in a cool place for the next four to six weeks. Here the temperatures should be between just below zero and four degrees. It can take up to ten weeks for the cotyledons to show.

    Acanthus in the pot

    The plants develop deep taproots and need a lot of space. Acanthus thrives in deep containers that have been adequately drained. Do not choose a pot that is too large, but transplant your Acanthus into slightly larger pots every year.

    Since the perennials love warmth, they are perfect for cultivation in raised beds, provided their longitudinal axis is laid out in a north-south orientation. The vertical wooden walls make optimal use of the sun's rays in the morning and in the afternoon.

    This is how the potting soil is made:

    • coarse-grained parts for a loose structure
    • ideally suited: lava gravel, expanded clay (19.73€) or gravel
    • loamy portions for water storage

    balcony

    Acanthus in a pot feels particularly comfortable on south-facing balconies with airy conditions. Potted plants should be watered regularly and thoroughly during the summer months. The perennials enjoy watering once a week.

    Pour acanthus

    Keep the substrate slightly moist. Acanthus enjoys moderate watering. The perennial tolerates slight drought well. Waterlogging should be avoided so that the roots do not rot.

    Fertilize acanthus properly

    Occasionally give the perennials plant decoction over the irrigation water. They strengthen vitality and make Acanthus more resistant to diseases and pests. In the spring you can work some rock flour (€14.13) or compost into the substrate. Further fertilization is not necessary.

    Properly cut acanthus

    The inflorescences remain in place over the winter. They are stable and act as a real eye-catcher during the gray season. In the spring, the perennial is cut back to the ground. The inflorescences can be placed in vases as cut flowers.

    How do I plant correctly?

    Ingrown acanthus perennials can be removed from their location with a lot of effort. Since the roots reach deep into the soil, the rhizomes are divided during transplanting. If you want to remove the perennials from a location, you must regularly dig up freshly sprouting rhizomes. Choose the location carefully before planting. Acanthus will do well if left undisturbed in one location for several years.

    hardy

    Although the species are considered hardy, winter protection is advisable. A thick layer of bark mulch and straw or spruce and fir branches protect the rhizome from frostbite. In snowy regions, the plants are optimally protected by a closed blanket of snow.

    Potted plants should be placed on an insulating base. This can be a styrofoam plate (€45.00) or a piece of wood. The pot is wrapped with fleece, jute or plastic wrap so that the substrate does not freeze. A rain-protected location prevents waterlogging in the substrate. You can also overwinter potted plants indoors. Place the bucket in an unheated room.

    fungus

    Occasionally, Acanthus is attacked by powdery mildew. The fungal spores spread in dry and warm conditions. They colonize weakened or diseased plants and leave a wipeable coating with a flour-like structure on the leaves. The risk of infestation can be reduced by a layer of mulch. It ensures constantly moist conditions in the substrate and increases the humidity.

    Acanthus does not bloom

    While the Hungarian Hogweed flowers reliably every year, its three ornamental relatives often show irregular flower development. If the perennials do not bloom, a severe winter may be the cause. Ground frost causes the rhizome to freeze back and partially die off. The damaged rhizomes sprout reliably, but the young plants need two to three years to flower. With a winter protection, the underground parts of the plant can be protected.

    tips

    All four ornamental plants can be distinguished by their leaves. The flowers are very similar. When buying, pay attention to the foliage if the variety has not been assigned to a parent species.

    sorts

    • Hollard's Gold: Acanthus mollis hybrid with white to light purple flowers, flowers between July and August. Up to 120 centimeters high.
    • White Lips: Acanthus hungaricus hybrid with a white crown and purple bracts, flowers from June to August. Up to 70 centimeters high.
    • Mornings Candle: Hubris from Acanthus mollis and spinosus. White flowers with purple bracts. Flowering time from July to August. Growth height up to 100 centimeters.

Category:

Herbs