As many of us are experiencing some very hot temperatures, we thought we would take a look at perennials that can take the heat and thrive. Many of these plants once established are low-maintenance and remember they come back every year. Some of these perennials are tender perennials meaning they are not winter hardy in colder climates. In cooler climates, they can still be grown as an annual.
Here are seven perennials that can take the heat:
Agastache – Agastache is also known as Anise Hyssop or Hummingbird Mint and is often grown in perennial gardens even though it is actually an herb. The plant will grow 2 to 4 feet high and in the summer is covered with pretty purple flowers. The flower blooms from early summer until fall. The Agastache plant is hardy in USDA plant hardiness zones 4 to 10. It is a prolific self-sowing plant and if it finds a place it really likes, it will come back for many years. It prefers rich, moist soil conditions in full sun and it’s leaves and flowers both have a licorice scent and can be steeped into a pleasant-tasting tea. Provide plenty of water when establishing the plants. They will be able to fend for themselves thereafter. The flower is a magnet for pollinators including bees, butterflies, and hummingbirds. Agastache blooms also make interesting dried flowers.
Evolvulus – The gorgeous blue flowers of Evolvulus will brighten your flower beds or containers. This plant is a member of the Morning Glory family, so the flowers will close in the afternoon. The plant is perfect for a bright sunny, dry spot as it is drought tolerant and it also is a spreader. It is hardy for zones 8 – 11. Bees and butterflies love the nectar-filled flowers and you will see them in your garden all afternoon. It is considered a perennial in southern regions of the country, in other regions it is an annual plant. Evolvulus can grow in partial shade, but a sunnier location is better. It prefers well-drained soil and does not like to be in wet soil for too long. If you live in a region where the plant is a perennial, you can prune it in early spring to encourage new growth.
Pentas – These sun-loving plants have star-shaped flowers that bloom all summer long. The bold-colored flowers come in a variety of colors including lavender, pink, purple, red, and white. The plant grows 18 to 36 inches tall. In warmer regions of the country, they are perennial and in other parts, they are considered an annual. Pentas need to be planted in a location where they get 6 – 8 hours of sun. These easy to grow plants do great in most types of soil, but need it to be well-draining. They do not like to be in soggy soil. Pentas look great in containers. They attract hummingbirds and butterflies. They are also deer and rabbit resistant.
Persian Shield – Persian Shield is a large, evergreen perennial known for its unique foliage. The leaves are an iridescent purple that shimmer with a hint of silver. The foliage also features bold green stripes along the veins. The leaves can grow 4 to 7 inches long and are 3 inches wide. The plant will grow 2 to 3 feet across and 3 to 4 feet tall. It looks great in mixed plant containers or perennial beds. For greater impact, try growing them with silver or chartreuse plants. In the winter, small violet flowers appear. If you don’t like them, just pinch them off. Persian Shield does well in humid climates, making it a great selection for summer gardens in Florida. Plant it in rich, well-drained soil where it can receive regular watering. It performs best planted in partial shade to full shade. It is hardy for zones 8 – 11. In colder geographies, it is a summer annual. The plant can also be adapted to a houseplant.
Passion Flower - Passion flower is also known as Passiflora or passion vines. There are over 500 species of this flowering plant. The flower has a tropical feel and comes in vibrant colors and some even produce edible passion fruit. These flowers are only open for one day. Most of these plants are vines but some are shrubs. The flowers range from ½ inch to 6 inches. These vines are found naturally in South America through Mexico. This plant is a tender vine, meaning it will not overwinter in many parts of the United States. Most varieties are hardy for zones 7 – 10. During a single season, the vines can grow up to 20 feet. For best performance, plant them in well-drained soil in full sun. It will look great planted along a fence or trellis. In cooler areas, you might want to mulch the roots to protect them in the winter. Passion flowers can be grown from seed or a cutting but you can also purchase them in a garden center.
Scaevola - Scaevola is a sun-loving flower that also goes by the name fan flower. It will grow 8 – 12 inches tall. The tiny petals of this delicate flower are arranged in a fanlike design. Each flower has 5 petals and the flowers grow in clusters around the stems. The flower is found in blue, pink, purple, and white. The foliage has small bright-green oval leaves with toothed edges. Scaevola is an Australian native plant that is heat tolerant and has almost no insect or disease problems. This plant does not need to be deadheaded. It is ideal for window boxes, hanging baskets, and containers as well as flower beds. Grow Scaevola plants in a location that receives at least 6 to 8 hours of sunlight daily in well-drained garden soil. This flower is not particular about soil type or pH, but they won’t tolerate soggy conditions. It is drought tolerant and a great selection for low-water gardens. The plant attracts bees, butterflies as well as other pollinating insects and is deer resistant. It is considered a tender perennial, hardy for zones 9 – 11.
Yucca – Yucca is an eye-catching tough plant. Looking to add drama to your landscape, consider adding this beautiful plant. The foliage is stiff and pointed. The leaves come in a variety of colors including blue, cream, gold, green, and variegated. In certain seasons, the foliage might be pink. Silvery green is the most often seen color. The foliage texture varies from thin, almost grass-like leaves to those that are thick and wide. The flowers develop on very tall stalks in masses of white and cream, and sometimes a light pink. They will blossom from spring to late summer. Many Yucca varieties are native to hot, dry geographies. They need well-drained soil or they will quickly rot and die. If you add them to your garden, make sure you pair them with other perennials that do not need continuous watering. They perform best in full sun, which makes the most intense colorations of variegates varieties as well as the most prolific flowers. If they do not get full sun, the plant is not as robust. If you live near the ocean, this plant is ideal as it has a high tolerance to salt. Most varieties can be easily grown in USDA Zones 7B – 10, there are some varieties that may be grown in as low a zone as 6. There are tropical species of this plant that can be brought indoors for the winter.
Do you have any heat-loving perennials to add to our list?
Persian Shield photos courtesy of Proven Winners.