Heat Tolerant Plants for Containers

Even in a heat wave, there’s no reason that summer can’t be every bit as colorful and filled with flowers as springtime. If your favorite flowers have stopped blooming in the grips of summer heat, it’s time to bring in some tried and true tropical flowering perennials to your container garden.

  • 01 of 07

    Lantana

    Lantana

    Steve Asbell

    It used to be that lantanas (Lantana camara) available to gardeners were weedy and somewhat unkempt looking, but today’s garden center offers a better-behaved assortment of trailing hybrids and species perfectly suited to growing as "spillers" in pots and hanging baskets. In addition to the more commonly found hybrids with red and yellow flowers, Lantana montevidensis (pictured) produces prolific lavender flowers on trailing stems. All lantanas are irresistible to butterflies—so much, in fact, that you might have a hard time getting a single photo of a full grown plant without finding a butterfly photo-bombing your shot.

    While lantanas are usually advertised as drought-tolerant plants for the garden, container-grown plants will wilt if the potting mix is allowed to dry out. Either treat them as annuals or try growing them in a sunny windowsill over winter. They are tricky as houseplants because they love humidity, but will easily rebound when planted back outdoors in spring.

  • 02 of 07

    Hibiscus

    High Angle View Of Hibiscus Blooming In Garden
    Maria Andreea Lavric / EyeEm / Getty Images

    It might be the first tropical or summer flower you think of, but there’s more to the hibiscus family than your classic garden variety red Chinese hibiscus (Hibiscus rosa-sinensis). ‘Haight Ashbury’ is grown just as much for its finely divided burgundy leaves (think Japanese maple) as it is for its matching burgundy flowers. ‘Snow Queen’ is popular for its variegated white, pink, and green leaves—the delicate coralline flowers are as impressive as any red hibiscus you’ll see.

    Each variety has a nice upright habit, making them excellent as centerpieces and focal points in a container garden. Be sure to give full-grown and arching specimens a little bit of support by inserting garden stakes in the container’s potting mix and loosely tie a loop of string around the stem. If you choose to keep hibiscus plants indoors through winter, be advised that they're very difficult to successfully grow indoors and are best kept in a greenhouse or sunny bathroom where they can get ample humidity.

  • 03 of 07

    Bottlebrush

    Bottle Brush

    Steve Asbell

    With sage green, velvety leaves and frequent bursts of intense red puffballs blossoms, Bottlebrush is a favorite flowering shrub. The dwarf selection known as ‘Little John’ (pictured) is a popular choice amongst container gardeners. Most bottlebrushes (Callistemon species) are ideal for training as small trees in containers but ‘Little John’ stays so compact and low that it may be used as a perennial or shrub amongst other plants in the container garden.

    Bottlebrushes are relatively drought-tolerant but should be watered thoroughly if grown in containers. Bring your plant indoors before the first frost and overwinter it as a houseplant in a cool and sunny room. It will continue to bloom sporadically until its grand finale of fireworks in spring.

  • 04 of 07

    Princess Flower

    Princess Flower Photo

    Steve Asbell

    The royal name of ‘princess flower’ wasn’t given to Tibouchina urvilleana by accident, and it would be a truly noble addition to your garden by virtue of its velvety cool green leaves alone. But when you start to see those silver and downy flower buds appear at the tips of each stem, stand back and enjoy the procession of deep purple blooms. Even the curled stamens take on a feminine quality if you imagine them as eyelashes. Often referred to as ‘spider flower’ in Latin America, the plant's dramatic intensity is matched by few other plants.

    Princess flower is available in a compact dwarf form, and its relative Tibouchina heteromalla has impressive fuzzy leaves over six inches wide. These tropical plants may bloom year-round when grown outdoors in a frost-free climate or greenhouse, but will otherwise bloom from May until January if overwintered indoors.

    Continue to 5 of 7 below.
  • 05 of 07

    Cuphea

    Cuphea llavea, Cuphea barbigera, Tiny Mice
    Neil Holmes / Getty Images

    With names like cigar plant (Cuphea ignea), candy corn plant (Cuphea micropetala) and batface flower (Cuphea llavea), you can already tell that these plants are lots of fun. Best of all, Cupheas all produce loads of narrow hummingbird-attracting blooms on upright stems throughout the hottest days of summer. Place taller ones at the back of a sunny container garden or use them in combinations where their finely-textured foliage and flowers can pop against broad-leaved "thrillers" such as cannas. 

  • 06 of 07

    Salvia

    Salvia Lecujam photo

    Kerry Michaels

    Hummingbirds and butterflies salivate over the wispy and boldly colorful blooms of salvia and so will you. The most common salvia offered as an annual is Salvia splendens, but when it's compared to the rest, it's rather boring. Instead, look for rainbow-colored salvia. Some favorites:

    • ‘Caribbean Coral’: fiery orange-red blooms
    • 'Mexican Bush Sage' fuzzy bright maroon spires
    • ‘Black and Blue’: luscious deep blue and purple flowers
    • Limelight’: feathery chartreuse-colored spikes
  • 07 of 07

    Ground Orchids

    container gardening picture of orchid

    Kerry Michaels

    Those delicate moth orchids (Phalaenopsis) that are so commonly grown as houseplants can also be grown outdoors in a shady spot during summer, but they're also just the tip of the iceberg when it comes to this flower. There are many terrestrial (ground-dwelling) orchids that would be perfectly content if planted in a sunny container garden, and they will add considerable exotic flair to your outdoor gatherings.

    Reed stem Epidendrum (Epidendrum radicans) looks like a big mimic of milkweed and pretty much blooms nonstop all summer whether grown in shade or full sun. The reedy stems may get lanky under their own weight by late summer, so tie them to garden stakes inserted into the potting mix for additional support.

    If you’re seeking a more behaved orchid, Philippine ground orchid (Spathoglottis plicata) is low-growing and bears colorful clusters of flowers ranging from deep pink to yellow atop graceful arching leaves. Both orchids are tender to frost but can be either grown as annuals or overwintered indoors as houseplants. 

Before you get started with one of these fabulous flowers, be advised that they are all tropicals and will turn to mush in the event of a frost or hard freeze. Either bring them to a sunny window before the first frost or treat them like annuals, collecting seed and starting from scratch in spring.

All of these plants will bloom in summer, and many will bloom from spring until fall. While these tropicals can tolerate drought in the landscape, container gardeners must keep them watered at all times to keep them from burning to a crisp in the hot sun. But don’t let the extra care stop you— they’re totally worth it.