Flowers that border your herb garden can be ones that have bright blooms, aromatic features or those that bring butterflies. Flowers bring color and visual interest to a very useful garden that tends to get sparse the more it is used for herb collecting. Choosing flowers for bordering an herb garden is really a matter of the gardener's personal choice, but here are a few favorite standards.
Wild columbine, Aquilegia canadensis, is from the buttercup family and is an easy-to-grow plant that attracts hummingbirds. Bell-like flowers are in red and yellow, 1 to 2 inches long, and contrast nicely against 4- to 6-inch-long fern-like leaves. Columbine can get 2 feet tall and 1 foot wide. Plant in any soil, in any light but total shade. Propagate via seed and grow in USDA hardiness zones 3 to 8.
Garden sage, Salvia officinalis, is from the mint family and is a fragrant perennial shrub that gets 2 feet tall and 2 feet wide. Leaves are oval, 3 inches long, wooly and smell like rosemary. Flowers can be lilac, white or blue in racemes. Plant this one in full sun in any soil with regular watering. Propagate via seed, leaf cuttings or root division. It is grown in USDA hardiness zones 5 to 10.
Rue, Ruta graveolens, is from the citrus family and is an evergreen perennial that is drought tolerant. It is also known as common rue or herb of Grace. This will get 2 to 3 feet tall and 2 to 3 feet wide with woody stems. Leaves are 3 to 4 inches long and they have a strong smell when bruised. Flowers are small and yellow, ½ inch long, and bloom in the summer. Plant this one in full sun in poor sandy soils. Propagate via seed or tip cuttings and grow in USDA hardiness zones 4 to 9.
Showy sedum, Sedum spectabile, is from the orpine family and is also known as balloon plant, showy stonecrop or everlasting. It is a perennial that will attract butterflies. This will get 2 feet tall and 2 feet wide with succulent leaves that are bluish green and 3 feet long. Pink star-like flowers are ½ inch wide in clusters that are 6 inches wide. Plant this one in sandy well drained soil in full sun or light shade. Propagate via root division, stem cuttings or leaf cuttings and grow in USDA hardiness zones 4 to 9.
Common yarrow, Achillea millefolium, is from the aster/daisy family and is also known as soldier's friend, sneezewort or milfoil. It is a butterfly attracting perennial that has grayish green fern-like leaves. Flowers are ¼ inch wide, white and profuse on 2 to 3 inch wide clusters. Plant this one in poor but well-drained soil with full sun. It may need staking. Propagate via division or seed and grow in USDA hardiness zones 3 to 9.