Red flowers make yards look bigger. White flowers are used in moon gardens. Serene blue flowers are great for meditation gardens.
Remember plant maintenance during plant selection. Petunias, for example, “melt” after a rainstorm, leaving an ugly mess behind; for aesthetic reasons, you’ll have to remove the spoiled flowers. So if you’re looking for a low-maintenance display of red, white, and blue flowers, petunias are one plant to avoid. Learn about a variety of plants with red, white, and blue flowers, ranging from annuals and perennials to vines and shrubs. Another reason why annuals are the preferred bedding plants is that they’re compact: It’s easier to appreciate a color scheme when the colors occur all on one level. Annuals are also cheaper than perennials, which is important if you need numerous plants. Salvia splendens is usually thought of as a plant with red flowers, but other colors are available. A common red-white-and-blue combination is red geraniums (Pelargonium), white salvias, and blue Ageratum. Salvia also comes in burgundy, pink, purple, lavender, salmon, and orange. Salvia splendens becomes 18 to 30 inches tall. Grow it in full sun. It has average water needs. A good cultivar for a red bee balm (Monarda didyma) is Cambridge Scarlet. What makes bee balm better than many perennials for color schemes is it’s a long-blooming perennial. It can grow up to 3 feet tall. Grow it in USDA plant hardiness zones 4 to 9 in full sun to partial shade. It likes quite a bit of water (it’s a good plant for wet areas). This perennial grows up to 3 to 4 feet tall. Suited to zones 3 to 10, Maltese cross likes full sun and has average water needs. Beauty of Livermere reaches 2 to 3 feet tall. Grow it in zones 3 to 7 in full sun. It has average water needs. Like bee balm, Oriental poppy is a good perennial to grow with annuals. The leaves disappear in summer, so annuals can fill the hole left over in your flower bed. Among the shrubs with red flowers, roses offer some of the best choices. There are many types of roses, and they come in an astounding variety of colors. Beating the traditional rap against the genus, Rosa, some kinds are surprisingly easy to grow. Candy Oh! is one such rose. It’s 3 to 4 feet tall and wide and grows in zones 4 to 9. It needs full sun and an average amount of water.
As part of a container garden, install it along the edge so it can spill over the rim. Grow it as the white filler between red and blue flowers in a landscape-berm planting. Treat it as a flowering ground cover for the summer.
Besides white, it comes in pink and purple. Plant sweet alyssum in full to partial sun and supply it with an average amount of irrigation. The Purity cultivar becomes 10 inches tall and is suited to zones 4 to 8. These sun-lovers don’t need as much water as the average perennial, once mature. Impatiens plants average 1 foot tall and wide. Keep them even shorter by pinching back young plants, which makes them grow bushier. Besides white, they come in coral, pink, purple, red, rosy-pink, orange, violet, and yellow. Besides its masses of small, white flowers, snow-in-summer sports silvery leaves. It likes full sun, an average amount of water, and soil that’s poor but drains well. It’s salt-tolerant. The two have similar needs and features:
Suitable for zones 4 to 9Best for partial sunSlightly above-average water needsLarge flower heads (9 to 12 inches across)4 to 5 feet tall and wide
That’s why flossflower (Ageratum houstonianum) is popular. This annual does bloom in other colors (pink, purple, lavender, and white), but it makes its living as a blue flower. Red geranium, white alyssum, and blue Ageratum are the traditional trio of red, white, and blue flowers for Americans who plant for Memorial Day and July 4th. The most creative designs vary not only in color and size but also in form and texture. Ageratum has something to contribute here, too. Its blue threads (the “floss”) give its flowers a fine texture to contrast with the coarser texture of petunias, etc. The height range of this annual is from 1 to 2 feet, but keep it around 1 foot tall through pinching. Grow it in full sun and give it a bit more water than most of your other annuals. Such similarities aside, they’re very different. Spanish bluebell (7 to 16 inches tall) is a bulb plant that can take sun in the North, whereas Virginia bluebell (up to 2 feet tall) is simply a perennial and always needs a lot of shade. Virginia bluebell’s flower is a richer blue than Spanish bluebell’s. Hibiscus syriacus Blue Chiffon (8 to 12 feet tall, 6 to 10 feet wide) can be grown in zones 5 to 8. It likes full to partial sun and an average amount of water. Blue Bird needs the same growing conditions. It’s smaller (8 to 10 feet tall and 4 to 6 feet wide) than Blue Chiffon, but the bigger difference is in flower color: Blue Bird is a richer blue.
