How to Grow Verbena in New Hampshire

Verbena is a perennial plant beloved for its vibrant flowers and ability to attract pollinators. Known for its resilience and adaptability, verbena can be a wonderful addition to gardens across New Hampshire. In this guide, we will explore how to successfully grow verbena in the unique climate of New Hampshire, covering everything from soil preparation to care and maintenance.

Understanding Verbena

Before you start your gardening journey, it’s useful to understand what verbena is and why it thrives in certain conditions. Verbena comprises several species, with Verbena bonariensis and Verbena officinalis being among the most popular for garden cultivation. These plants produce clusters of small flowers that come in various colors, including purple, pink, white, and red.

The flowers are not only attractive but also functional; they attract butterflies, bees, and other beneficial insects to your garden. Additionally, verbena has medicinal properties and has been used traditionally for various ailments.

Choosing the Right Variety

In New Hampshire’s climate, it is crucial to select the right variety of verbena that can withstand the local weather conditions. Here are a few popular types:

• Trailing Verbena (Verbena x hybrida): This variety spreads beautifully and is excellent for hanging baskets or as ground cover.
• Tall Verbena (Verbena bonariensis): Known for its height and airy structure, this type can grow up to 4 feet tall and makes an excellent focal point in mixed borders.
• Common Verbena (Verbena officinalis): A hardy perennial that can survive the colder months.

Selecting a variety suited for your garden’s specific needs will enhance your chances of success.

Soil Preparation

Ideal Soil Conditions

Verbena thrives in well-draining soil with a slightly acidic to neutral pH (6.0 to 7.0). The soil should be rich in organic matter but not overly wet, as verbena is susceptible to root rot.

Soil Amendments

To prepare your soil:

1. Clear the Area: Remove any rocks, weeds, or debris from the planting area.
2. Test the Soil: Use a soil test kit to check pH levels and nutrient content. Local extensions or garden centers often offer testing services.
3. Amend as Needed: If necessary, amend the soil with compost or well-rotted manure to improve drainage and nutrient content.
4. Tilling: Till the soil to a depth of about 12 inches to ensure aeration.

Planting Verbena

Timing

In New Hampshire, the best time to plant verbena is in late spring after all danger of frost has passed. Typically, this is around mid-May but can vary depending on local weather conditions.

Planting Process

1. Spacing: When planting verbena, space them about 12-18 inches apart to allow for air circulation and growth.
2. Digging Holes: Dig holes that are twice as wide as the root ball of the plant. The depth should be such that the crown of the plant is level with the soil surface.
3. Transplanting: Carefully remove the plant from its container and place it in the hole. Fill in around the roots with soil and gently pack it down to eliminate air pockets.
4. Watering: After planting, water thoroughly to help establish roots.

Watering Needs

Frequency

Verbena plants prefer their soil on the drier side; overwatering can lead to root rot. During hot summer months, water deeply once a week or more frequently if there is no rain.

Watering Technique

• Drip Irrigation: Consider using drip irrigation systems or soaker hoses that deliver water directly at the root zone without wetting foliage.
• Morning Watering: Water early in the morning when temperatures are cooler. This approach minimizes evaporation and allows plants to absorb moisture effectively.

Light Requirements

Verbena flourishes in full sunlight, requiring at least six hours of direct sun each day. When choosing a location for your verbena plants:

• Look for areas with minimal shade from trees or buildings.
• Ensure there’s good airflow around the plants to prevent disease.

Fertilization

While verbena does not need heavy fertilization, providing nutrients can enhance flower production:

1. Type of Fertilizer: Use a balanced fertilizer with equal parts nitrogen, phosphorus, and potassium (e.g., 10-10-10).
2. Frequency: Apply fertilizer every 4-6 weeks during the growing season starting from early summer until fall.
3. Avoid Over-fertilizing: Too much fertilizer can lead to lush foliage at the expense of flowers.

Pest and Disease Management

Common Pests

While generally resilient, verbena can be susceptible to various pests:

• Aphids: Small green bugs that suck sap from plants; use insecticidal soap if infestations occur.
• Spider Mites: Fine webs on leaves indicate spider mites; increase humidity or treat with neem oil or insecticidal soap.

Diseases

Diseases such as powdery mildew or root rot can affect verbena under specific conditions:

• Ensure proper spacing between plants for airflow.
• Avoid overhead watering to reduce humidity on foliage.

If diseases occur:
– Remove affected plants immediately.
– Apply appropriate fungicides if necessary.

Pruning Verbena

Regular pruning helps keep verbena healthy and encourages bushier growth:

1. Timing: Prune during spring when new growth begins or after flowering ends in fall.
2. Technique: Remove dead or wilted flowers (deadheading) to promote new blooms.
3. Shape Maintenance: Trim leggy stems back by one-third to maintain shape and promote denser foliage.

Winter Care

In New Hampshire’s cold winters, it’s essential to protect your verbena:

1. Mulching: Apply a layer of mulch around plants in late fall to insulate roots against freezing temperatures.
2. Covering Plants: In particularly harsh winters, consider covering plants with burlap or frost cloths when temperatures drop significantly.

Conclusion

Growing verbena in New Hampshire can be a rewarding experience that adds color and vibrancy to your garden while attracting beneficial wildlife. By understanding soil preparation, proper planting techniques, watering needs, pest management strategies, and winter care practices, you can cultivate these beautiful plants successfully. Embrace these tips as you embark on your gardening journey with verbena – creating a flourishing outdoor space that you’ll enjoy for years to come!