Commonly seen growing wild along steep banks, the common periwinkle (Vinca minor) adds greenery and interest to otherwise bare spaces. While periwinkle may not be the largest plant in the garden, it more than makes up for it in its usefulness.
This reliable ground cover plant is a prolific spreader. In its preferred partial shade position, a single plant can achieve a spread of about 8 ft. Despite its extensive spread periwinkle is a low growing plant, rarely exceeding 4 inches in height. Through its masses of broad green foliage delicate blue flowers emerge during the April and May months.
Also known as creeping myrtle or creeping vinca, periwinkle grows as a spreading shrub in USDA Zones 4 to 8. While common periwinkle is an attractive plant, there are over 30 varieties available. These include cultivars producing blooms in a range of colors and others that are grown for their variegated foliage.
Reliable, colorful and attractive, this guide to planting vinca minor in your garden takes you through everything you need to know.
A small plant with an extensive growth habit, creeping myrtle is a popular ground cover option. It is also an attractive ornamental plant.
Be warned vinca minor is difficult to remove, particularly once established. This can make it problematic. It also means that it can appear low down on invasive species lists.
Check the plants status in your area before planting. If you are unable to plant vinca minor, other plants that provide ground cover in shady positions include:
- creeping juniper
Different Periwinkle Varieties
There are over 30 different varieties of vinca minor currently available flowering in shades of blue, purple, lavender and white. Take the time to find one that suits your garden. Specialist nurseries may offer a wider range of plants than your local garden store.
The name periwinkle is often applied to two varieties of plant:
- Vinca Major
- Vinca Minor
Vinca major is the larger of the two cultivars and is hardy in USDA Zones 7 to 9. Vinca minor, also known as common periwinkle or creeping myrtle grows in Zones 4 to 9.
While Vinca major and minor are separate plants, they have many growing conditions and preferences in common.
There are a number of vinca minor cultivars available. Take the time to find a variety that suits your garden.
The cultivar Flore Pleno is an unusual double flowering variety, reliably producing purple colored blooms. Another purple flowering variety is Atropurpurea. This cultivar is prized for its dark purple blooms which emerge through the plant’s lush green foliage.
The showy Bowlesii cultivar is known for its vigorous clump-like growth habit and large, dark blue flowers. Another eye catching variety is Variegata. While its blue flowers are similar to many other vinca minor varieties, the interest here is in the foliage. Variegata produces masses of attractive green and yellow variegated foliage.
If you want a plant that is less busy, try the reliable Alba cultivar. Alongside its masses of foliage, Alba produces attractive, small white flowers.
While vinca minor can be grown from seed it is a slow process. It is quicker and easier to grow from nursery transplants or divisions. Take the time to find an attractive and healthy plant that suits your growing situation.
Remember vinca minor has a large spread and a vigorous growth habit. Even just a few plants can easily fill a large space.
Don’t confuse vinca minor with annual periwinkle, Catharanthus roseus. Despite being called periwinkle, this is a different plant with different needs and habits.
Where to Plant
Periwinkle does best in dry, partial shade positions. The plants thrive when growing as ground cover beneath taller plants. They also tolerate deep shade positions, but growth may be slower.
Avoid planting creeping myrtle in full sun. This may cause foliage to burn.
These plants prefer rich, acidic soils but can tolerate poorer soil if cared for correctly. A soil test kit is a quick and easy way to find out the makeup of your soil. Overly alkaline soils can be amended in a number of ways.
Work the soil over before planting. This is the perfect time to amend or enrich poor soils.
Creeping myrtle’s spreading habit means that you should avoid planting near other small plants. If you do not regularly take steps to prune and control the plants spread, it quickly overtakes and smothers other plants.
While it is commonly used for groundcover, an interesting alternative periwinkle use is to plant it as a climber, training it to grow up a trellis. Using the plant as a climber is an interesting way to create privacy in an outdoor space.
How to Plant
Plant vinca minor either in spring or early fall.
Work the soil over well before planting. If your soil is poor or heavy work in rich compost. Manure or peat moss can also be used. This enriches the soil and improves drainage.
Use a shovel to dig a hole large enough to hold the plant’s root system. The top of the root ball should be level with the soil when placed in the hole.
Remove the plant from the pot. Take care not to damage the root system as you do this. If the plant is difficult to remove, squeeze the sides of the pot to loosen the soil. You should then be able to slide the plant out of the pot.
Position the plant in the hole and carefully backfill, taking care not to sink the plant. After planting water deeply.
Keep the soil evenly moist for 6 to 10 weeks after planting. This helps the roots to establish themselves.
If you are planting more than one creeping myrtle plant, space the plants 12 to 18 inches apart.
Planting in Containers
You can also plant periwinkle in containers. Allowing the plants to spill over the edge of pots can look particularly attractive. Planting in containers also helps to contain vinca minor’s vigorous growth habit.
Your chosen pot should be clean and have drainage holes in the bottom. Don’t worry about planting creeping myrtle in too large a pot. The plant eventually spreads and fills the space.
Fill the pot with fresh potting soil. Adding some crocks to the bottom of the pot before you fill it with soil can further improve drainage.
Plant as described above.
Caring for Periwinkle
Once planted this is a pleasingly easy plant to care for. The most time consuming task is keeping the plant’s growth habit in check.
As it grows, particularly in the weeks after planting, remove any weeds that may emerge. There are a number of useful tools that are designed to make weeding your garden easier. Once established vinca minor shades out and deters weeds from emerging.
Mulching around young or growing plants helps the soil to conserve moisture. When plants are small or young, a layer of mulch can also help to suppress weeds.
When to Water
Once established and mature vinca minor is surprisingly drought tolerant. Water when the top inch of soil is dry to the touch.
When compared to other plants, periwinkle has a relatively shallow root system. This means that it may require more regular watering. The Yoyomax Soil Moisture Meter provides a reliable way of monitoring the moisture content of your soil. Regularly using a moisture meter enables you to know exactly when to water your plants, eliminating the danger of overwatering plants.
Planting in self watering pots is an easy way to keep plants hydrated.
Fertilizing Creeping Myrtle Plants
Regularly fertilizing your plants is particularly helpful in poor soils. If you are growing in a rich soil, the plants won’t require fertilizer.
To fertilize, apply a balanced plant feed once a month. A regular application helps to enrich the foliage and can also encourage more flowers to emerge.
The exact amount of fertilizer you need to apply varies depending on how many plants you are fertilizing and the area they cover. Consult the information on the side of the fertilizer packet before applying. A pump sprayer provides an easy way to fertilize a large area.
Liquid fertilizers are easily incorporated into watering routines.
Using a watering can enables you to easily incorporate liquid or water soluble fertilizers into your watering routine.
This is not a frost tolerant plant. In colder climates you will need to protect the plants from wind and water damage when the temperature is above freezing. Failure to do this can cause winter burn.
Move plants growing in containers inside when temperatures fall towards 50 ℉. Plants in the ground can be protected from light frosts by covering with a horticultural fleece. The Agribon Frost Blanket not only protects plants from cold weather it is also permeable. This means that while your plants are protected from frosts, air and moisture is able to pass through the blanket, keeping your plants healthy.
How to Prune Creeping Myrtle
Regularly prune periwinkle plants during the growing season to keep them in their place. Regular pruning also helps to prevent the plants from becoming invasive.
Cut back runners as well as lanky or overly long stems to their point of origin. This contains the plant’s growth habit and keeps it looking neat. Pruning runners can be done at any point during the growing season.
Periwinkle roots quickly if stem nodes are allowed to come into prolonged contact with the soil. These rooted runners can be cut away from the plant and grown on as new plants.
Vinca minors extensive growth habit means that you need to prune it regularly during the spring and summer months.
Particularly large spreads of creeping myrtle can be mown back in the spring. Set the mower to its highest setting before mowing.
In late summer tall plants can be cut down to about 6 inches in height if they are in danger of becoming overgrown.
Do not place cut vinca minor plants on your compost heap. They are likely to root and continue growing. Instead cuttings should be destroyed.
Pruning away dead or damaged growth also helps to keep the plant looking neat.
Deadhead or pinch out flowers as they fade. This encourages the plant to produce more blooms, extending the flowering period. It also helps to keep the plant looking neat and tidy.
Always use sharp garden scissors or shears to prune. Sterilize tools before and after use to prevent disease from spreading throughout your garden.
Don’t prune periwinkle during the fall and winter months. Pruning encourages new, tender growth to emerge. This can be easily damaged by the winter weather.
How to Propagate Periwinkle
Periwinkle can be grown from seed but this is a slow process. The easiest and quickest way is to take divisions of an established plant.
Divisions are best taken on a cool day in the fall. Water well a few days before dividing.
Before you begin, decide how large a division you want to take. Use garden scissors or shears to cut back any stems that are in the way. Cut all the stems that attach your division to the main plant.
Use a sharp shovel to dig all the way around the clump that you want to lift. There is no need to dig too deeply, these plants have shallow roots. With the shovel, carefully lift the division from the ground.
Plant the division in its new position as soon as possible. After planting gently firm down the soil and water thoroughly.
Propagation via Cuttings
Periwinkle plants can also be propagated by taking stem cuttings.
Cuttings can be taken at any time during the growing season. Water the plant an hour before taking the cutting.
Use garden scissors to cut away a 2 to 6 inch long tip from a stem that is yet to flower. Your chosen cutting should be healthy and have at least 3 sets of leaves. Cut away the leaves from the bottom half of the stem.
Fill a pot with fresh potting soil. You can also root your cuttings in pots filled with an equal combination of peat moss and sand or perlite.
Water the rooting medium and allow the water to drain away. Make a hole in the center of the pot and plant the cutting, the lower leaf nodes should be covered. Firm the rooting medium down.
Place the pot in a propagator. The Tabor Tools Propagator has air vents in its lid. This helps you to maintain humidity levels and also means that air is able to circulate around your growing plants.
Position your propagator in a warm place, filled with indirect sunlight. Check the cutting regularly and water when required. Aim to keep the soil evenly moist. Roots form within 3 weeks.
Once roots have formed, allow the cuttings to grow on, gradually transplanting into larger pots. Plant out in the garden when the last expected frost date has passed.
Common Pests and Problems
A pleasingly robust plant with a long lifespan, periwinkle doesn’t suffer from many issues.
In humid or wet climates the plants can develop root rot or canker. Infected plants should be dug up and destroyed. Prevent root rot by amending heavy soils to improve drainage. This should be done before planting.
Botrytis blight can cause leaf spots to form. It may also cause flowers and foliage to fade. Blight strikes in moist, cool climates. Copper or sulfur fungicides can be used to treat blight.
To prevent blight from developing space out and regularly thin your plants. This prevents overcrowding and helps air to circulate around the foliage.
Keeping the foliage as dry as possible when watering also helps to prevent blight. This can be difficult with spreading plants such as periwinkle. Instead try watering only in the early morning. Watering early in the day gives the foliage time to dry out before the cooler evening temperatures arrive.
Easy to care for and deeply attractive, this is a reliable addition to any garden.
Pleasingly easy to care for, the broad, attractive foliage and dainty flowers of periwinkle provides a great ground cover option. Its creeping habit can also be used to create a floral waterfall effect.
An attractive sprawling plant, periwinkle has long been an ornamental garden favorite. As long as you are prepared to deal with the plants rapid growth habit it is also surprisingly easy to grow. Flowering in the spring and often again in the summer this plant is a colorful way to introduce ground cover or low interest to a garden.