Verbena Bonariensis Plant Care

Table of Contents

Recently we spoke about caring for the Verbena plants, but today we want to provide you with a special care article on the Verbena bonariensis plants. These perennials look great and are easy to grow with their purple flowers.

More About Tall Verbena Plants

The Verbena bonariensis belongs to the Verbena family, and the Verbena bonariensis common name is:

  • Purpletop Vervain

  • Tall Verbena

  • Argentinian Vervain

  • Pretty Verbena

The species is native to South America, but you find them growing globally. As the plant Verbena self-seed, it is an invasive species in certain parts of the world. But why should you grow Verbena?

Firstly the main benefit of the plant is that it adds color to any garden. You get a display of small purple flowers that stand out among other plants on the wiry stems. Furthermore, it attracts pollinators like butterflies that will pollinate your garden.

Another benefit of growing Verbena bonariensis is that it grows as a companion with other plants. When you mix it with other perennials, you get a vibrant color display brightening up the landscaping or even the patio.

Verbena Bonariensis Care Guide

Verbena Bonariensis care card

When you plant Verbena directly into the ground, the best time to do this is in spring, but for container planting, you can grow them at any time. Another notable thing is that the plant has an upright clump forming growth with wiry branched stems.

You find them blooming from early spring, mid-summer, right through to the first frost. Another fantastic thing is that they make beautiful cut flowers and receive a Garden Merit award as a long flowering plant.

The best part is you can grow Verbena in hanging baskets indoors or outdoors in the garden with its stunning blooms and lance-shaped leaves.

The Best Soil Conditions For Purple Top Vervain

gardening soil

To grow Verbena, provide them with well-drained soil acidic with a neutral 5.8 to 7.2 pH level. The plant is not picky about soil, but it must drain well. So, if you have clay soil, we recommend adding some coarse sand or a potting mix to prevent waterlogging and root rot.

For ground planting, adds some compost and leaf mold to make the soil lightweight. The same applies to hanging baskets.

Lighting Needs For Verbena Plants

Verbena Bonariensis in full sun and partial shade

The Verbena bonariensis are hardier compared to the tender varieties and fairly drought tolerant. You can grow your plant in full sun to display new blooms from spring to the last frost. Your plant needs at least six hours of direct sunlight as shady locations reduce the flowering.

Watering Your Verbena Bonariensis

As important as it is to have well-drained soil and full sun, these plants thrive in moist soil but not soggy soil. The plant is fairly drought tolerant, but it can attract spider mites if drought-stressed. While overwatered plants attract botrytis blight which is root rot.

Fertilizer For Your Flowering Plant

plant fertilizer

These plants are not heavy feeders but can do with some feeding throughout the flowering season. Using a slow-release flower fertilizer, you can provide the plant with a monthly application. But if you grow Verbena in containers, we recommend using a water-soluble feed.

Doing this for indoor and outdoor plants with help with new growth.

Humidity and Temperature

Verbena Bonariensis temperature and hunidity requirement

Hardier types, like the Verbena bonariensis flowers, thrive in a sunny climate during the growing season. But the purple top can also survive in colder climates as they self-seed well. They flourish during the flowering period, with enough space to provide air circulation in the garden.

Still grown in small pots growing indoors, they can even survive winter colds.

Seasonal Checklist For Your Plants

Some notable things you can do at certain times of the year are as follow:

Spring

  • In early spring, you can sow the seeds indoors.

  • You can cut down your plant’s overwintered stems during spring.

  • Or you can plant Verbena seedlings after the last frost date in the garden.

Summer

  • During early summer, you can take cuttings to propagate your plant.

  • Summer is also a great time to deadhead the spent flowers during the flowering season to help prevent self-seeding.

Fall

During autumn, you can layer some mulch over your tender varieties.

Winter

At the end of autumn, if you decide to uproot the tubers, you can place them in containers to overwinter. Or you can bring your plants indoors when growing in containers.

Propagation of Verbena Bonariensis

As these plants freely self-seed, you usually do not have to propagate them. But if you do, you can easily take some stem cuttings to place in small containers. Again, we recommend taking healthy stems with no flowers or buds.

  1. Take good quality soil and prepare a container for your cutting.

  2. Then make a hole the size of the cutting and water it well after planting.

  3. Then place your cuttings in a warm shady spot and not in direct light.

  4. Only water the soil when you feel it is dry and if you can use a spray bottle to prevent it from becoming overly saturated.

  5. It should take about four weeks for your plant to root; after two months, you can transplant it outdoors.

Pruning Your Plant

You can trim your plants once or twice per season as it helps stimulate new growth and blossoms. It also helps to keep your plant tidy.

Verbena Varieties

In the Verbena genus, you can find several garden varieties to grow as perennials.

Verbena hastata

The Verbena hastata is a slender perennial with branched spires and blooms pink flowers.

Verbena rigida

It is a low-growing Verbena that grows well in hanging baskets with magenta to purple flowers that form clusters from spring to fall.

Verbena officinalis var. grandiflora

The Bampton blooms small pink flowers on flushed purple stems.

Verbena Bonariensis Diseases and Pests

Your Verbena bonariensis flowers are resistant to pests and diseases, but as with most plants, they can still become infested. The first concern is powdery mildew, a fungus developing on the leaves. It looks like mold with a powdery finish.

If your plant has powdery mildew, we recommend removing and destroying them as the fungus spreads fast. The disease happens in moist conditions, and if not enough air circulation is present.

It would be best if you also cared when watering, and best not to water over the crown but at the base of the plant. Another concern is leaf spot that looks like tiny brown/red spots. To prevent it from happening, follow the same procedures as for the powdery mildew.

Or you can treat your plant with a fungal spray if not severely infested. Rust is also a concern as it also develops with red/brown spots on the leaves. You can remove the infected leaves and use a fungicide when caught early.

Pests that can bother your plant are spider mites, aphids, and scale. You can treat your plants with insecticidal soap, neem oil, or a good fungicide.

Frequently Asked Questions

Yes, you cut back your plant in spring to provide your plants with new growth. You do this by removing the old stems at the base.

In the USDA hardiness zone 7 to 11, you can grow Verbena as a perennial; in the cooler climates, you grow them as an annual.

The potted Verbena can survive winter when you take it indoors. Yet, if grown outdoors, you can uproot the entire plant to place it in a container for overwintering.

You can find the plant sold at local nurseries. Or you can browse through the Plantly collection to find Verbena seeds here.

Whether you want to buy, sell or simply reach out to other plant enthusiasts, Plantly is the right place to be!

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