Growing conditions in Maryland vary. The Eastern shore has a humid, subtropical climate with hot summers and mild winters. The extreme western part of the state consists of mountains with mild summers and cold winters. The Piedmont area runs between them with fertile rolling landscapes. The U. S. Department of Agriculture places the state in zones 5 through 8. The best flowers to grow in Maryland are native plants acclimated to your location.
The marsh marigold (Caltha palustris) forms a round clump of green leaves, topped with 12-inch high bright yellow flowers in early spring. The plant becomes dormant in late summer. The marsh marigold prefers moist to wet soil and adapts well to the warm swampy areas near the coast. Because it is poisonous, deer usually leave it alone.
The shooting star (Dodecatheon meadia) also appreciates moist or wet soil. It prefers full or partial sun and sends pink or yellow star-like flowers up 12 inches high above the green rosette-forming leaves. Plant these as borders or edgings. You can use them in cut flower arrangements.
According to North Carolina State University, moss phlox (Phlox subulata) grows well in the Piedmont and mountain areas. It grows only up to 9 inches high and forms a dense mound of needle-like foliage with tiny pink, red, blue or white flowers in the spring. Moss phlox prefers full sun and well-drained soil. Plant it as a groundcover.
The native bloodroot (Sanguinaria Canadensis) thrives in the woodland areas. The white flowers come up early in spring, followed by the 8-inch high foliage as the flowers disappear. This plant prefers partial or full shade and moist soil. Plant these as edgings or mass them in flowerbeds.
Great White Trillium
The great white trillium (Trillium grandiflorum) forms a dark-green foliage clump 18 inches high. White flowers bloom in spring, turning pink as the blossom ages. This plant prefers moist soil and partial or full shade. It adapts well to rocky areas. The New Perennial Club states that the great white trillium is resistant to rabbits and deer.