Bigleaf periwinkle is used by many as a ground cover. The bright blue flowers then ring in spring every year. Here are tips for planting and care.
Profile of bigleaf periwinkle:
Scientific name: Vinca major
Plant family: dogbane family (Apocynaceae)
Other names: large periwinkle, greater periwinkle, blue periwinkle
Planting time: spring and autumn
Flowering period: April to May
Location: partially shaded to shady
Soil quality: sandy to loamy, moderately nutritious, humus rich
These information are for temperate climate!
Use in: ground cover, planters, underplanting, natural garden, forest garden
Winter hardiness: hardy, USDA Plant Hardiness Zones: 7 (-15 °C / +5 °F)
Bee and insect friendly: Yes
Plant characteristics and classification of bigleaf periwinkle
Plant order, origin and occurrence of bigleaf periwinkle
The bigleaf periwinkle, is one of the members of the dogbane family (Apocynaceae). The plant has spread from the western and central Mediterranean area to the Middle East. However, the subshrub is rarely seen in nature. If so, then in shady places in the woods, near hedges and streams.
Characteristics of bigleaf periwinkle
The extremely robust large evergreen spreads with creeping shoots up to one meter (40 in) long. Bigleaf periwinkle quickly weaves a 20 to 30 centimeters (8 to 12 in) high, loose green polster made of curved dark green leaves. The twines close to the ground conquer the beds as they grow, as their nodes form roots and anchor themselves when they come into contact with the soil.
The shiny, leathery leaves of large periwinkle reach a size of 3 to 7 centimeters (1.2 to 2.8 in). Their shape resembles an egg, with the leaf base looking heart-shaped and the blade tapering forward. The large periwinkle, as the name emphasizes, differs from the lesser periwinkle (Vinca minor) by larger leaves and longer shoots. The leaves are deep dark green. But there are also two-tone varieties with white and yellow-green foliage.
The bright purple-blue flowers of the bigleaf periwinkle bloom in April and May; a second time in autumn, but mostly only sporadically. The approximately 5 centimeters (2 in) large flowers unfold in the leaf axils on long stems above the foliage. The variety ‘Alba’ is an exception. It shines with white flowers. Vinca major is popular with bees, bumblebees and hover flies during its heyday.
Bigleaf periwinkle forms two dry, often different sized, follicle fruits per flower, which are connected to the base. The bare, rough seeds are bumpy.
Bigleaf periwinkle – cultivation and care
The large periwinkle loves partially shaded to shady places, but also tolerates sunshine well if it is planted in moist soil.
The evergreen subshrub tolerates different pH values: from moderately calcareous to slightly acidic. Bigleaf periwinkle also likes well drained, humus-rich, sandy-loamy garden soils. The plant does not grow well on wet and compacted soils.
Planting bigleaf periwinkle
In general, the bigleaf periwinkle can be planted all year round in frost-free weather. Experience has shown that spring and autumn are the best times of the year to plant in the garden bed. Five to seven plants are sufficient for an area of one square meter (10 sq ft.), as the subshrub spreads well and quickly. It is therefore advisable to keep a distance of 30 to 40 centimeters (12 to 16 in) when planting.
Some home gardeners tend to water excessively and frequently. Which all too often leads to the death of many plants. The supply of water should be part of the ritual, especially on hot summer days, but only where it is really necessary. The large periwinkle is also extremely sensitive to waterlogging. If the roots of the plant are often exposed to standing moisture, the risk of root rot increases. Infected plants rarely recover from this fungal disease and die completely. Bigleaf periwinkle should always be watered as soon as the first 2 centimeters (0.8 in) of the soil have completely dried off. If possible, avoid watering in the midday heat.
In addition, many forget that there can be bottlenecks in the water supply even in winters with black frosts. If the weather forecast announces sunshine and frost for several days, it is advisable to water the large periwinkle as a precaution.
Mixing compost under the soil in spring and late summer is usually sufficient. Wilted leaves, which get together around the large periwinkle before winter, also contribute to as an important supply of nutrients. In the winter months you should completely avoid the use of fertilizers.
The evergreen ground cover reacts calmly to a pruning and then quickly starts up again, provided the trimmed shoots retain enough leaves. The best time to use the scissors is before the new shoots in early spring. The cut back ensures a perfect shape or limits the urge to spread of the plant. Little corrections with the scissors are basically possible throughout the year.
Vinca major is forgiving if you briefly walk over its branches during garden work.
The bigleaf periwinkle can be propagated vegetatively very well. To do this, the subshrub is divided in spring. Or you can separate well-rooted side shoots and replant them in another place. It can also be propagated relatively easily by cuttings.
Cut off several shoots about 15 centimeters (6 in) long from strong growth. Except for 3 to 4 upper pairs of leaves, the cuttings are completely defoliated. Then put 2/3 of the cuttings into the ground and keep it sufficiently moist. You can tell whether the rooting was successful by the formation of new shoots and buds. Don’t lose patience, frequent setbacks are not uncommon.
The fast-growing tendrils lying on the ground form roots. These can be separated from the mother plant with a sharp knife and planted elsewhere. This action is also suitable for refilling bald spots within the polster.
Diseases and pests
Aphids and other harmful insects are rarely found on the leathery leaves of the evergreen. Gluttonous nudibranchs also avoid the poisonous plants, but the number of fungal diseases is increasing. With the right care you can promote the resilience of the subshrubs.
Dark brown pustules on the underside of the leaves indicate a fungal infection. In the course of the disease, the leaves roll up, the pustules crack and release the powdery fungal spores. Cut off infected parts of the plant generously and dispose of immediately with household waste. Under no circumstances put the remains on the compost, because the rust fungus can spread even further via dead shoots and leaves. In order to protect nearby subshrubs, you should apply a fungicide from a specialist dealer or a swill made of horsetail on the leaves. In addition, watering with nettle or horsetail swill strengthens the plants.
Stem and leaf rot
Another disease caused by fungal pathogens also affects the leaves and shoots of the bigleaf periwinkle. The stems turn black and die, the black fruiting bodies of the fungus can often be found on withered leaves. Immediately remove all infected parts of the plant and apply a mix of water and milk (ratio 10:1) or spray a swill made of horsetail on the leaves.
The bigleaf periwinkle can withstand temperatures of up to -15 °C / +5 °F without complaint. In very rough locations it should be covered with brushwood or similar. Particular caution is required with young plants and variegated varieties. The subshrubs usually recover quickly.
Use in the garden
The large periwinkle is a beautiful ground cover, even on large areas. It is suitable for underplanting light trees, but also creates beautiful accents in the tub. Since the bigleaf periwinkle grows very lush, it needs partners at its side who know how to assert themselves, such as cranesbill species or various ferns. It also looks nice when Vinca major is planted in groups with spring flowers, such as Balkan anemone (Anemone blanda), wild garlic (Allium ursinum) or spring crocus (Crocus vernus).
- Vinca major ‘Variegata’ blooms blue and catches the eye all year round with its white-green leaves. It is a little more sensitive to frost
- Vinca major ‘Alba’ differs from the species in the way that it has very large white flowers. The variety is best shown against a dark background
- Vinca major ‘Hirsuta’ grows very quickly and is harder than the species. It flowers blue and the evergreen foliage is very delicate. With a height of 15 centimeters (6 in), the variety is well suited for small beds
- Vinca major ‘Reticulata’ has yellow variegated leaves, but only retains its intense variegation in light areas. It sets nice accents in buckets