Hoary Vervain (Verbena stricta)
– Full to part sun.
– Medium-dry to dry soil.
– About 2 feet tall. Will lean towards the sun and might sprawl. If you want this plant to always stand straight and tall, consider using a plant support.
– Blooms blue/purplish blue from late June through September. To get the longest period of bloom, deadhead the completely finished flowers by looking carefully at each stem and cutting just above a set of leaves where a small bud is forming. (For photographs demonstrating this, click on this link: Purple Coneflower (Echinacea purpurea).) If you check and deadhead every 2 weeks or so, the plant will continue blooming and blooming. It will be one of your longest blooming perennials. This is a wonderful trait. The butterflies will thank you!
– This plant will self-seed. I have not found it to be a prolific self-seeder in my garden, but from reading about the plant, other gardeners have found volunteers all over their garden. Be aware you could have either experience. I would welcome volunteers in my garden! You can also collect seeds. They require a cold stratification period of 60 days, but after that, they germinate quickly. Seeds can be planted in fall or spring.
– No fertilizer is needed.
– Hoary Vervain can be transplanted during its first growing season in your garden. Choose your spot carefully as in the second year, transplanting will be more difficult. You will need a sharp shovel and the ability to dig a large and fairly deep hole as this plant has an extensive and deep root system. After the second, year, in my opinion it cannot be transplanted. The tap root is too deep and the root system is too extensive.
– This plant is both deer and rabbit resistant.
– As far as I know, it is generally pest and disease free. I have grown this plant for about 10 years and the dozen I have planted together in my garden have never had any problems.
– Beneficial insects and smaller butterflies will use this plant and sparrows, finches, and juncos will feast on the seeds.
I truly love this plant for its long bloom. Summertime is heavy with yellows and oranges. The blue flowers are a welcome contrast. I would recommend you plant several of these plants together – if you plant just one, the plant can get lost among all the other summer bloomers. It is beautiful when massed together. I have 12 in a large plot along my driveway and love to see them every time I come home.
Plants that are good companions are Asiatic lilies, Shasta Daisies (Leucanthemum × superbum), Black-eyed Susans (Rudbeckia hirta), Ironweed (Veronia), and Coneflowers (Echinacea).