Ammi Majus Companion Plants

Annuals

• Like bishop’s weed, annual companions germinate, bloom, go to seed and die all in the same growing season. Calendulas tolerate dry soil and thrive in full sun. These 24-inch-tall annuals bloom from summer through fall with yellow, orange and red blossoms. Zinnias flower in a range of colors, from white to red. Their single or double blooms appear from spring through frost and are attractive components in flower arrangements. Zinnias thrive in sunny sites with rich, well-drained soil.

Perennials

• Perennials live for at least three seasons, though most die to the ground over the winter and regenerate in the spring. For spring color, plant blue wild indigo (Baptisia australis), a 3-foot-tall perennial that blooms with spikes of purple-blue flowers. It grows best in well-drained soil and sun to light shade. Cinquefoils (Potentilla x hybrida) add bright-yellow hues to the garden in summer. These 2-foot-tall perennials thrive in full sun and well-drained soil and have dark, five-parted foliage. Velvet sage (Salvia leucantha) blooms from summer through autumn with deep-pink and white flowers. It prefers sun and well-drained soil and grows to 3 feet tall.

Ornamental Grasses

• Many ornamental grass species grow best in full sun exposures and well-drained soil. Pink hair grass (Muhlenbergia capillaris) grows to 3 feet tall and thrives in sun to light shade and dry, sandy soils. This clumping grass has fine, dark and lustrous foliage and produces airy, pink inflorescences. Variegated tuber oat grass (Arrhenatherum elatius subsp. bulbosum “Variegatum”) tolerates dry to wet soil and grows to 12 inches tall. It grows slowly and has pointed, white-green striped foliage.

Ground Covers

• Ground covers keep weeds from growing around bishop’s weed and help prevent soil erosion and water run-off. Sun-loving varieties include leadwort (Ceratostigma plumbaginoides), a perennial that grows to 12 inches tall and has green foliage that turns coppery-red in fall. It produces bright-blue flowers in late summer and grows well in sun to partial shade and well-drained soil. Creeping gardenia (Gardenia jasminoides “Radicans”) grows from 12 to 24 inches tall and spreads to 3 feet. This evergreen has tough, lustrous foliage and produces fragrant flowers from late spring through early summer. It tolerates heat and drought and prefers sun or partial shade exposures.