Yes this is another plug for native plants and no I am not talking about red sunflowers. The yellow in the title does indeed refer to sunflowers which include the variety Helianthus angustifolius or Swamp sunflower which is a native of Maryland. To discover which plant is the red you will have to read the article by Christina Pax which I came across on The Master Gardeners website.
Perennial sunflowers (Helianthus spp.), like their annual sunflower cousins, have a cheerful yellow bloom. They are typically smaller both in flower and stature, although some are still quite tall. They generally begin blooming in late August-September, then continue well into October and sometimes even November.
Finches and chickadees love the seeds of perennial sunflowers. As a group, they prefer good, full sun; a moist, sandy soil; and will usually require some room, as they can become tall. They typically have both opposite leaves (on the lower part of the stem) and alternate leaves (just below the flower clusters).
Helianthus decapetalus, Thin-leaved sunflower, or Ten-petaled sunflower, blooms from July through October. It likes full or part sun, prefers a sandy soil, and grows from two to five feet tall, depending on the circumstances. Helianthus divaricatus, or Woodland sunflower, is a good sunflower candidate for less sunny locations, as its name implies. It also prefers less moisture than the other sunflowers, preferring dry to moist soil. Both of these are native to Maryland.
Helianthus angustifolius, Swamp sunflower, has a pointy-petaled, yellow, daisy-like bloom with a dark center. This Maryland native blooms late August through October. Swamp sunflower prefers a moist, sandy soil of average fertility.
Butterflies will visit these flowers, and if you let them go to seed, birds will devour the seed heads. Once established, a single clump can take command of six to nine square feet of space in your garden, so plan accordingly! Swamp sunflower typically grows 5-7 feet tall, and is somewhat vulnerable to slumping over during a heavy rain, but if you cut it back in midsummer you should be able to keep it more compact and eliminate any need for staking. Another flower to consider would be Helen’s flower?
See more at The Master Gardeners