How to Grow Verbascum Tall Flowers for a Stunning Garden Display

If you’re looking to add a touch of elegance and vibrancy to your garden, Verbascum—commonly known as mullein—is an excellent choice. These tall flowers are known for their stunning spikes and lush foliage, making them perfect for creating an eye-catching garden display. This article will guide you through everything you need to know about growing Verbascum in your garden, from choosing the right species to providing proper care.

Understanding Verbascum

Verbascum is a genus that includes about 250 species of flowering plants. Most people recognize it for its tall, flowering spikes that can reach heights of up to 6 feet. The flowers, which bloom in summer, are typically yellow, white, or purple, attracting a variety of pollinators like bees and butterflies.

Key Features of Verbascum:

• Height: Many species can grow between 2 to 6 feet tall, creating vertical interest in the garden.
• Flowers: The blooms can be yellow, purple, or white and are arranged in dense spikes.
• Leaves: Most Verbascum species feature soft, fuzzy leaves that are usually silvery-green.
• Sun Requirements: These plants thrive in full sun.

Choosing the Right Species

Before diving into cultivation, it’s essential to determine which Verbascum species best suits your garden. Here are a few popular varieties:

1. Verbascum thapsus (Common Mullein)

This biennial plant is often seen in wildflower gardens. It features tall spikes of yellow flowers and grows to about 6 feet tall. It attracts various pollinators and is drought-resistant.

2. Verbascum olympicum

This perennial species boasts large yellow flowers and can reach heights of up to 4 feet. It blooms in late summer and is ideal for creating a visual impact.

3. Verbascum chaixii

Known for its charming lavender flowers, this perennial grows about 3 feet tall and prefers slightly moist soil, making it ideal for a woodland garden.

4. Verbascum blattaria (Moth Mullein)

This species features pale yellow flowers and can reach heights of up to 4 feet. It is known for its unique, moth-like appearance.

5. Verbascum speciosum

This variety showcases stunning purple to violet flowers and grows about 3 feet high. It’s attractive to butterflies and a great addition to mixed borders.

Site Selection and Soil Preparation

1. Location

Verbascum plants prefer full sun, which means they need at least six hours of direct sunlight a day. Choose a spot in your garden that is free from shade and competing plants.

2. Soil Quality

Well-drained soil is crucial for Verbascum. They prefer slightly alkaline to neutral pH levels. If your soil is heavy or clay-like, amend it with sand or compost to improve drainage.

3. Soil Testing

Before planting, consider conducting a soil test to determine nutrient levels and pH. This will inform your fertilization strategy.

4. Site Preparation

Clear the area of weeds and debris. Loosen the soil to a depth of at least 12 inches, incorporating organic matter for improved soil health.

Planting Verbascum

1. When to Plant

Verbascum can be sown either in the spring after the last frost or in the fall for earlier bloom in the next growing season.

2. Sowing Seeds

• Direct Sowing: After preparing the soil, sow the seeds about 1/4 inch deep and space them at least 12 to 18 inches apart. Lightly cover with soil and water gently.
• Indoor Seed Starting: If starting seeds indoors, plant them in seed-starting mix about 8 weeks before the last frost date. Transplant into your garden after the risk of frost has passed.

3. Transplanting Seedlings

If you started your Verbascum indoors, transplant seedlings when they are about 4-6 inches tall and have at least two true leaves.

Watering and Fertilization

1. Watering

Verbascum plants thrive on minimal water once established. However, while they are young, ensure they receive consistent moisture. Water deeply but infrequently to encourage deep root growth.

2. Fertilization

Verbascum doesn’t require heavy fertilization. Applying a balanced, slow-release fertilizer in spring can promote healthier growth, but it’s often sufficient to rely on the nutrients naturally present in well-prepared soil.

Pruning and Maintenance

1. Deadheading

Once the flowers fade, remove spent blooms to encourage the growth of new flowers. This will also help prevent the plant from self-seeding if that’s not desired.

2. Cutting Back

In late fall, you can cut back the plant to ground level to prepare for winter. This will help prevent disease and pests from taking hold in the foliage.

3. Pest and Disease Management

Verbascum is relatively pest-resistant. However, watch for aphids and spider mites. If necessary, treat with insecticidal soap. Good air circulation and proper spacing can prevent foliar diseases.

Propagation

Verbascum can be propagated through seeds or division. Division can be done in spring or fall for established perennials.

1. Seed Collection

If you wish to collect seeds, allow some flower spikes to mature fully. They will turn brown before you harvest, and seeds can then be stored in a cool, dry place for the next planting season.

2. Dividing Plants

To propagate through division, carefully dig up an established plant, separate the root ball into smaller sections, and replant immediately.

Landscaping Ideas with Verbascum

Verbascum can be an impressive centerpiece or a perfect backdrop for other plants. Here are a few creative ideas:

1. Mixed Borders

Integrate Verbascum with shorter perennials like coreopsis or daylilies to create multi-layered garden beds.

2. Pollinator Gardens

Being attractive to bees and butterflies, Verbascum can be part of a pollinator garden alongside other nectar-rich plants.

3. Cottage Gardens

Incorporate them in a charming cottage-style garden, where they can grow alongside wildflowers and other ornamental plants.

4. Vertical Interest

Use Verbascum to create height in a flower bed, pairing them with groundcovers or lower plants to add depth.

Seasonal Care

1. Winter Protection

In colder climates, consider mulching around the base of the plants to protect the roots from harsh winter conditions.

2. Spring Cleanup

As spring approaches, remove any dead plant material. This will make way for new growth and improve air circulation around the plants.

Conclusion

Verbascum is a stunning addition to any garden, offering dramatic height and beautiful blooms. With minimal care, these striking plants can thrive, providing beautiful displays and attracting pollinators. By selecting the right species, preparing your soil, and providing adequate care, you can create a breathtaking garden space filled with these elegant flowers. Happy gardening!