Long-Blooming Color for the Drought Tolerant Garden
Verbena is a great selection for Bay Area gardens. Their bloom time is very long – from early spring into late fall. Verbenas are either bedding annuals or perennials that originate from the Americas or Asia. The common Verbena (officinalis) is from Europe and has long been regarded as a divine herb through history. It is also used in herbal medicine as a sleep aid.
Verbena blooms are tight clusters of tiny flowers, although some of the annual flowers are a little larger. The inflorescence is usually produced above the foliage, and flowers range in color through the cool hues of blue, purple, and lavender to white, pink, and red. The annuals are often groundcovers and trailing plants. The perennials are herbaceous or semi-woody and are mainly low-growing, although Verbena bonariensis sends up tall stalks of flowers 3-6′ high.
Ornamental verbenas are drought tolerant but will do better and bloom more profusely with some summer water. The perennials can be short lived. Often their demise is premature due to bad drainage in heavy soils. Therefore, although verbena, like rosemary and lavender, can tolerate nutrient-poor soil, it does require excellent drainage. Verbena’s ideal growing locations are spilling over retaining walls and in hillside gardens in the full, hot sun.
In order for Verbena cultivars to thrive, well-composted amendment should be added to the soil to improve drainage in heavy clay soil. It will also help to plant them on a small berm or mound so that excess water will drain away from their roots. They should be watered at the root zone, avoiding overhead water on the foliage.
For maximum blooms, they can be cut back several times during the growing season (about 1/4 of the foliage) to stimulate more flower production. When they are cut back, it will help to add some slow release fertilizer, such as Osmocote Flower and Vegetable. Pollinators are attracted to their abundant nectar.
Verbena bonariensis ‘Lolipop,’ also known as Purpletop or Brazilian Vervain is a fantastic selection for the garden. Unlike the straight species V. bonariensis which has tall, beautiful, purple flower stalks that shoot up in summer, it is a dwarf so the flower stalks are shorter (up to 2′) but still striking and airy and don’t need to be staked. It’s a great choice for wildlife and pollinator gardens, as well as planting in pots to brighten up a patio. USDA Zones: 6-10.
Verbena lilacina ‘De La Mina’ is an excellent choice for the garden. It forms a 2′ high by 4′ wide beautifully rounded mound which blooms with bright lavender-purple flowers in spring and then sporadically through the summer. Near the coast it needs full sun, but in the hotter, inland areas, it can tolerant part shade. Butterflies will flock to this plant, so it’s the perfect choice for a wildlife or pollinator garden. USDA Zones: 7-10.
Planting and Care for Verbenas
- Plant in full sun.
- Plant in soil with excellent drainage.
- Amend soil with compost.
- Water regularly until established, then infrequently.
- Mulch around plants to conserve water and suppress weeds.
- Fertilize with Osmocote in the Spring.
- Cut back and fertilize during the growing season to stimulate more flowers.
- Cut back foliage but not wood in winter for fresh new growth in the spring.