15 Flowers That Start With R: Make Your Home and Garden Radiate 

Flowers that start with R can make your garden and home radiate joy. These flowers may be different in terms of their classification and growth requirements, but they will surely add a mark of beauty to their surroundings. Continue reading to discover some of these trusted plants.

Flowers That Start With R

1. Red Valerian (Centranthus Ruber)

The Red Valerian is a bushy wood-based and clump-forming perennial plant. It is well-branched and popularly grown for its showy and ornamental star-shaped flowers. Each bloom lasts only one to two days, but this plant has the longest blooming season in its family. Other names for the valerian plant are Fox’s Brush, Kiss-Me-Quick, Jupiter’s Beard and Devil’s Beard.

• Size: The shrub can grow 2–3 feet (30–60 centimeters) tall and 18–24 inches (46–61 centimeters) wide. However, you can prune it to a preferred size.
• Temperature and USDA hardiness zone: You should grow this plant in zones 5–8. Ensure that it grows at 60–75 degrees Fahrenheit (16–24 degrees Celsius).
• Humidity: You can easily grow the valerian plant in average humidity.
• Light: The shrub prefers full sun, but it can tolerate partial shade.
• Soil: The substrate should dry quickly. Grow this plant in the sand. 
• Watering: This plant has average watering needs.

2. Rose Mallow (Hibiscus Moscheutos)

This is a beautiful and fragrant flower that attracts beetles, bees, and butterflies to your garden. The Rose Mallow produces white to purple blooms that have hot pink centers and white pistils. Other names for the hibiscus are Eastern Rosemallow and Crimson-Eyed Rosemallow. It starts flowering in mid-summer and stops around early fall.

• Size: This hibiscus can grow to reach 3–7 feet (0.9–2.1 meters) in height and have a spread of 2–4 feet (0.60–1.20 meters).
• Temperature and USDA hardiness zone: Zones 5–9 are ideal for the plant while 60–90 degrees Fahrenheit (16–32 degrees Celsius) is optimal.
• Humidity: You should protect the Rose Mallow from the wind. Grow it in above-average humidity.
• Light: This flower needs six or more hours of sunlight daily.
• Soil: While it prefers well-drained soil, it can grow in still waters.
• Watering: Ensure that the soil is always slightly moist.

3. Red Hot Pokers (Kniphofia Spp.)

Here is a very beautiful flower with brilliantly orange, yellow and red torch-like flowers. The flowers are held upright on long and strong stalks. Red Hot Poker plants are herbaceous and perennial. This plant which is native to South Africa can be aggressive growers, so ensure to prune them often.

• Size: This beautiful plant can reach 3–4 feet (0.91–1.20 meters) tall and 2–3 feet (0.6–0.9 meters) wide.
• Temperature and USDA hardiness zone: Grow the hot kniphofia plant in zones 5–9. Ensure that it grows at 60–85 degrees Fahrenheit (16–27 degrees Celsius).
• Humidity: You can easily grow this plant in average humidity.
• Light: This plant prefers full and direct sun.
• Soil: Grow it in soil that quickly becomes dry after watering.
• Watering: Water the plant less frequently as it matures.

4. Rain Lily (Zephyranthes Spp.)

Here is a very simple-looking, but beautiful, flower. This plant produces yellow, white, or pink flowers according to the variety. It is native to the Western Hemisphere and other nearby regions. If you live close to a pond, this is the flower for you.

• Size: This little plant can grow from 6–12 inches (15–30 centimeters) tall.
• Temperature and USDA hardiness zone: The ideal USDA hardiness zone for rain lilies are zones 7–11. Grow the plant in warm places with around 65–90 degrees Fahrenheit (18–32 degrees Celsius).
• Humidity: While it can survive below average humidity, it grows best at around 60 percent humidity.
• Light: Lilies prefer full sun.
• Soil: Their soil should be organically rich and mildly acidic. It should be well-draining.
• Watering: Liles prefer wet substrate, but they can survive drought.

5. Rattlesnake Master (Eryngium Yuccifolium)

This is a beautiful perennial herb from the same family as parsley plants. It is native to the tallgrass prairies of eastern and central North America. Its name comes from the look of its white flowers as well as its use as a medicine to treat the bites of a rattlesnake.The beautiful rattlesnake plant is resistant to deer, rabbits, and other mammals.

• Size: The rattlesnake plant grows to reach 2-5 feet (0.6–1.5 meters) tall and 2 feet (0.6 meter) wide.
• Temperature and USDA hardiness zone: Grow this beautiful herb in zones 4–9. It tolerates from 50 to 85 degrees Fahrenheit (10–29 degrees Celsius).
• Humidity: It can tolerate a wide range of humidity. Grows best in places with 40 percent humidity or more.
• Light: This plant needs full sun to grow. Ensure that it gets at least five hours of sunlight daily.
• Soil: The substrate should be retaining moisture, yet be well-draining. Grow this plant in loam soil.
• Watering: Water the plant so that the soil is never fully dry.

6. Regal Geranium (Pelargonium Grandiflorum)

Check out this beautiful annual plant with hot purple, pink, white, red, or bicolor flowers with their white edges. The geranium plant comes from a large cosmopolitan family with around 11 genera and 800 species. You need to compliment the look of your garden with this very beautiful plant that is also super easy to grow.

• Size: The geranium plant can grow 12–15 inches (30–38 centimeters) tall.
• Temperature and USDA hardiness zone: Grow the plant in warm regions, from zones 10 and above. It grows best at 70 degrees Fahrenheit (21 degrees Celsius) or higher.
• Humidity: Ensure that the humidity levels never fall below 50 percent.
• Light: Grow the plant in partially shaded locations so that the hot summer sun does not burn its leaves.
• Soil: The soil should be very fertile and well-drained.
• Watering: Keep the soil evenly moist so that the geranium plant can grow with speed.

7. Rex Begonia (Begonia Rex)

This is a beautiful plant with beautiful leaves. While it is not grown for its flowers, the leaves are the centerpiece as they have spiral patterns made of dark green and light green colors. The Rex Begonia plant’s leaves can also be red or purple according to the variety and growing conditions. This plant is native to Arunachal Pradesh and southeast China.

• Size: 12–18 inches (30–46 centimeters) tall, similar spread
• Temperature and USDA hardiness zone: Zones 10–12 are optimal for the growth of the begonia. Grow it between 60 and 70 degrees Fahrenheit (16–21 degrees Celsius).
• Humidity: Humidity levels around or above 50 percent are ideal.
• Light: This plant can tolerate partial shade to full shade. It grows well indoors.
• Soil: The ideal pH of the plant ranges from 5.7 to 6.2. You can use a general-purpose potting mix.
• Watering: Water the plant often, but do not overwater them.

8. Red Campion (Silene Dioica)

The Red Campion is a semi-evergreen perennial that forms bold clumps of downy, spoon-shaped leaves. It is native throughout most of Europe. This flower is not just pretty, it is also simple and requires just a little maintenance.

• Size: The beautiful plant can grow 2–3 feet (60–90 centimeters) tall and 2 feet (60 centimeters) wide. You can prune it to your desired size.
• Temperature and USDA hardiness zone: Grow campions in zones 5–8. Ensure that it grows at 55 degrees Fahrenheit (13 degrees Celsius) or higher.
• Humidity: Grow it at 50 percent or higher levels of humidity.
• Light: This plant required dappled or partial light. Do not grow it in full sun.
• Soil: The ideal substrate for rose campions is clayey, moist, heavy, and boggy.
• Watering: Ensure that the soil is consistently moist.

9. Red Osier Dogwood (Cornus Sericea)

Here is a very colorful shrub. The Red Osier or Red Twig Dogwood is a deciduous plant that has rounded and spreading forms and produces beautiful twigs. It is native to North America and is characterized by the vibrant colors of its branches.

• Size: Red Osier Dogwoods can grow 6–9 feet (1.82–2.74 meters) tall and 8–12 feet (2.4–3.6 meters) wide. You have to prune them to your preferred size.
• Temperature and USDA hardiness zone: The plant grows best in zones 3–8. Do not grow it below 45 degrees Fahrenheit (7 degrees Celsius).
• Humidity: It can grow in average or above-average levels of humidity.
• Light: The Red Twig Dogwood grows best in full sun, but can tolerate partial shade.
• Soil: The substrate should be rich and retain moisture.
• Watering: According to the season, you should water the plant once to three times weekly.

You should grow this beautiful plant outside in plain soil as it adds a lot of color to the snow in winter.

10. Rosemary (Salvia Rosmarinus)

Rosemary is a very popular plant with evergreen, fragrant, needle-like leaves. It produces pink, white, blue or purple flowers and it is native to the Mediterranean region. You can grow the rosemary plant for its beauty and health benefits.

• Size: Rosemary plants reach 3–5 feet (0.91–1.5 meters) in height and 2–5 feet (0.6–1.5 meter) in width.
• Temperature and USDA hardiness zone: Grow the plant in USDA zones 7–11 and make sure that the soil temperature is around 70 degrees Fahrenheit (21 degrees Celsius).
• Humidity: Rosemary plants can tolerate a wide range of humidity, but make sure that the levels are above average.
• Light: Grow your rosemary in full sun.
• Soil: The substrate should be loamy and slightly acidic. You can enrich it with coffee grounds.
• Watering: Keep the soil consistently moist.

11. Rue (Ruta Graveolens)

The Rue plant produces yellow flowers and is grown as a herb and ornamental plant. It is a woody herb with blue-grey leaves with a pungent smell. The rue plant is not just simple and beautiful, it attracts butterflies and other pollinators to your garden.

• Size: The plant can grow up to 2 feet tall and 2 feet (60 centimeters) wide.
• Temperature and USDA hardiness zone: Grow the Rue plant in zones 4–10. You can leave them outside in winter as they are winter-hardy.
• Humidity: 50 percent or higher levels of humidity are ideal for rue flowers.
• Light: Make sure that your plants have up to six hours of daily sunlight.
• Soil: Grow Rues in loamy soil that is rich in humus.
• Watering: While the plant can tolerate dry soil, you want to keep the soil consistently moist.

12. Rainbow Hedgehog Cactus (Echinocereus Rigidissimus)

This beautiful cactus grows a short and thick stem. It produces pink flowers above the stem. Its stem has a white base and a pink top. You should grow this very cute cactus in pots indoors.

• Size: The Rainbow Hedgehog Cactus grows to reach 12 inches (30 centimeters) in height and 5 inches (13 centimeters) in diameter.
• Temperature and USDA hardiness zone: Grow the beautiful cactus in zones 9–11. It should grow at 65–85 degrees Fahrenheit (18–29 degrees Celsius).
• Humidity: You want to keep the humidity levels below average for this plant.
• Light: Ensure that your cactus gets six or more hours of sunlight every day.
• Soil: Make use of a general-purpose potting mix for this cactus.
• Watering: Wait until the soil is dry before you water your Rainbow Hedgehog.

13. Rose of Sharon (Hibiscus Syriacus)

The rose of Sharon is a type of hibiscus plant that produces white or blue flowers. The flowers have hot purple centers and white or cream pistils. This plant is native to Korea and other countries in Asia. It is a deer-resistant plant. You should control the size of this plant by pruning it regularly.

• Size: These plants can reach 8–12 feet (2.4-3.6 meters)  in height and 6–10 (1.8–3 meters) in width.
• Temperature and USDA hardiness zone: Grow your rose of Sharon in zones 5–8. Ensure that the plant grows above 55 degrees Fahrenheit (10 degrees Celsius).
• Humidity: The plant should grow in humidity levels above average.
• Light: It prefers full sun, but it can tolerate partial shade.
• Soil: Grow it in rich loam soil.
• Watering: While it is drought-tolerate, it prefers moist soil.

14. Rocktrumpet (Mandevilla Spp.)

Here is a beautiful plant with red hot flowers. It is native to Mexico, Southwestern United States, Central America, South America and the West Indies. Its flowers have five petals and the leaves are green. This is a fast-growing plant, especially when you grow it in the right conditions.

• Size: The Rocktrumpet plant grows to reach 3-10 feet (0.91–3.04 meters) tall and 3–4  feet (0.91–1.2 meters) wide.
• Temperature and USDA hardiness zone: Grow the beautiful plant in zones 10-11. Make sure that it grows at 60 degrees Fahrenheit (16 degrees Celsius) during the day and 50 degrees Fahrenheit (10 degrees Celsius) at night.
• Humidity: Average humidity is ideal for the plant.
• Light: The plant prefers full sun, but can grow in partial shade.
• Soil: Make use of loam soil when growing rocktrumpets.
• Watering: Ensure that the soil is never dry.

15. Rockcress (Arabis)

Here is a beautiful mat plant that can be purple, white, yellow, or pink according to the variety. It blooms in summer and attracts many beautiful insects such as butterflies. It originates from the Mediterranean region.Grow the beautiful plant outdoors in slopes, beds, garden edges and borders.

• Size: Rockcresses grow just 4–9 inches (10–23 centimeters) tall, but can spread 1–2 feet (30–60 centimeters) wide.
• Temperature and USDA hardiness zone: This plant grows best in USDA hardiness zones 5–7. Make sure that it grows at 45 degrees Fahrenheit (7 degrees Celsius) at least.
• Humidity: The humidity levels should be around average.
• Light: Grow the plant in full sun. However, you can grow it in partial shade.
• Soil: It prefers to grow in rocky, sandy, dry substrates.
• Watering: This plant has low watering needs.

Which beautiful flowers that start with R will you grow?

Conclusion

Flowers are beautiful and enchanting and evne more so when you grow them based on an arrangement. Many gardeners arrange their flowers based on their starting alphabets of the flower names and you can do that, too.

Flowers that start with R such as Russian Sages, Red Hot Pokers, Rainbow Hedgehog Cactus and Rockcress are not just radiant, they are also reputable. Which ones would you like to grow?

• Author
• Recent Posts

Evergreen Seeds

If you are looking for help gardening you’ve come to the right place! We love gardening and we want to share this love with you. Join our dynamic garden community.

Latest posts by Evergreen Seeds (see all)

• How Long Do Hibiscus Flowers Last: Ways To Elongate - May 24, 2023
• Aeroponics vs. Hydroponics: Comparison of Two Planting Ways - May 24, 2023
• Monstera Deliciosa Light Requirements: The Ideal Conditions - May 21, 2023