Do you have a blank spot that needs filling or a border that needs a little pizazz? Tropical summer bulbs are a quick fix. Corms and tubers planted in spring will grow by leaps and bounds during the summer bringing color, pattern and texture to the garden.
Many summer bulbs have lovely blooms, but look at the foliage too. The patterns, textures, and sizes create interest without much maintenance.
Rex Begonia – One of the most interesting plants when it comes to fabulous looking foliage. Available in shades of greens, white, burgundy, red, pink, silver and deep maroon-black. The patterns are almost endless. There are spirals, concentric circles, dots, stripes and shields. In addition to these variations there are different leaf shapes, textures, and stem colors. With names like Escargot, Iron Cross, Fireworks, Denver Lace, Capricorn, Miami Storm, Fire Flush and Mimi Boston how could you go wrong?
Hardy to zones 10 and 11, these plants prefer shady, humid conditions and rich, aerated soil with plenty of organic matter. Too much water and fertilizer and you will have a very unhappy plant. Soggy soil will lead to rot and high fertilizer will burn the foliage.
Calla Lily (Zantedeschia)– Grown mostly for its Art Deco style flower that blooms white, pastels, vibrant red, purple or yellow with a very narrow red margin. While the flowers are quite beautiful, the upright glossy leaves are what I am drawn to. In addition to bright green some varieties boast foliage with white centers, polka dots or green and yellow stripes.
Hardy to zone 9 an ample layer of mulch applied in the fall can get these plants through winter in zone 8 or possibly zone 7 where the temperature is not likely to fall below 10 degrees F. Otherwise dig the rhizomes when frost threatens and store them indoors or bring in the plant to grow as a houseplant. Calla Lilies like a moist, almost wet soil and warm temperatures and will grow in full sun (partial afternoon shade in the South.)
Canna – With its large, majestic stature and foliage, the beautiful blossoms of these plants almost go unnoticed. The tropical looking foliage with its large leaves, upright growth and interesting colors make a huge statement in the garden. Look for foliage that is purple, purple with green veining, yellow and green stripes and one of the most striking I have seen has burgundy, green, yellow and red/orange stripes. A few varieties I like include ‘Tropicana’, ‘King Humbert’, ‘Pretoria’ and ‘Black Knight’.
Hardy to zone 7, cannas grow from a rhizomatous rootstock that allows it to spread slowly outward from where it is planted. They prefer full sun in most locations but partial shade in regions where sunlight is intense may help keep the flowers from bleaching out or the foliage tips from burning. Cannas prefer a rich soil high in organic matter that drains well but stays consistently moist. They are heavy feeders. If your cannas begin to look ratty, it’s a sure sign that it needs to be fed or that the soil is too dry. You can grow cannas in containers but the containers will need to be large. As they become pot-bound they become weak and need to be divided and repotted. Cannas are root hardy in places where the soil does not freeze and can survive in air temperatures down to 0 degrees. In areas where the temperature may drop below 10 degrees, adding deep mulch will help protect the roots by keeping the soil surface from freezing.
Colocasia, Alocasia, Xanthosoma – Collectively known as elephant ears, these plants have large, fleshy leaves in solid green or purple/black. Many varieties have interesting variations in color with splotching and veining patterns of green, white and purple/black. Reaching anywhere from 2 to 6 feet or taller some show a distinctive, upright growth pattern while others are more spreading. Look for names like ‘Black Magic’ (burgundy-black foliage), ‘Chicago Harlequin’ (green foliage randomly blotched with lighter green), ‘Illustris’ (green foliage overlaid with black with lime green veins and margins) or ‘Lime Zinger’ (chartreuse foliage). Elephant ears can be planted in a summer border or grown in containers on the porch or patio.
Elephant ears are sub-tropical or tropical plants but some are hardy as far north as zone 7b. They prefer a bright, indirect light or partial shade. The leaves may scorch in full sun or become too green in deep shade. They generally thrive in hot, humid conditions as long as they receive consistent moisture. They prefer a moist, rich, deep, organic soil. Be sure to feed them often as they are heavy feeders.
Oxalis – A favorite plant of many, commonly called the Shamrock plant because of the clover-like leaves. Oxalis is available in green, white/silver, burgundy or purple. You can select oxalis solid colors, interesting patterns or variegations. The flowers range from white, yellow, pink, orange and red. Oxalis can be tucked into your flower borders, grown in containers on the porch or patio and also as a houseplant on a sunny windowsill. Their diminutive size fits easily into smaller spaces and in the front of borders where they will show off throughout the summer. These little bulbs will bloom on and off from spring until fall.
Fairly petite in size oxalis range from two to 16 inches tall and depending on species they are tender, half-hardy or hardy perennials to zone 6. Oxalis can grow in full sun in temperate climates. If you garden where summers are hot give it some afternoon shade or plant it in light, dappled shade. These little bulbs have a preference for well-drained soil that is a little on the acidic side. They are drought tolerant but do water them during extended periods without rain.
Caladium – Gardeners choose caladiums for their long lasting, colorful foliage that adds interest to lightly shaded areas. Color combinations include various shades of red, pink, white, green with colored midribs and contrasting margins. The leaves are heart shaped and many have contrasting patterns. They are a mid-sized plant perfect for planting in clumps in a border or in containers. Look for the varieties ‘White Christmas’ (white leaves with green veins), ‘Pink Beauty’ (pink leaves with dark pink veins and green margins), ‘Frieda Hemple’ (red leaves with green margins)or ‘Brandywine’ (deep red leaves).
Growing 18 – 24 inches tall, caladiums perform best in moist, well-drained soil in partial shade. They enjoy warm weather but do not tolerate dry conditions. Caladiums are only hardy in zones 10 to 11. Everywhere else they should be treated as an annual or dug up after the first frost. If you choose to dig up your caladiums allow the tubers to dry thoroughly, and then layer the tubers in dry peat or vermiculite and store them in an area that remains around 50 to 60 degrees F. Check the tubers occasionally to make sure they are plump but dry.