These bulbs keep the party going all summer long
Tuberose, a summer-blooming bulb with a unique fragrance, looks great in a garden or as cut flowers. (Stock imageTMS / May 23, 2013)
While these early bloomers provide us with much needed garden color after a long winter, many gardeners overlook the plethora of summer-blooming bulbs that add interest to the garden long after the last daffodil has faded away.
Summer-blooming bulbs can help fill those gaps in the garden when early flowering perennials have finished and the dog days of summer have many gardens looking tired and devoid of color.
Just like their cool-season cousins, summer bulbs are incredibly easy to incorporate into garden schemes. There are dozens of varieties to choose from, some suited for shade and others that relish the hot summer sun. Some are cold-hardy, while others hail from warm climates and must be dug at the end of the season before a freeze. Those that need to be dug are easy to store over the winter for replanting the following year.
Here are a few summer-blooming bulbs to consider adding to your garden this season:
Perhaps the queen of all garden plants, the Asiatic lily is understandably the most popular of all summer-blooming bulbs. Their large upward or sometimes outward facing flowers have an intoxicating fragrance that perfumes the air on warm summer days. They are available in a variety of pinks, reds and whites, and some are streaked with yellow or white or speckled with black spots.
Asiatic lilies vary in height depending on variety. Short and stout ones are perfect for the front of a border, while others, such as the majestic white 'Casa Blanca,' grow upwards of 5 feet tall. Asiatic lilies prefer to grow in full sun and well-drained, rich soil.
Lilies produce roots along their stems between the bulb and the surface of the ground. This helps support these tall plants, keeping them from toppling over. To allow them ample space to grow these specialized roots, plant the bulbs 8 to 10 inches deep.
Lilies of all types prefer cool soil and therefore are well suited for planting in mixed borders, which allows other plants to shade their roots.
Another summer bulb planted for its fragrance, Polianthes tuberosa, is one of my favorites. Depending on the variety, tall stalks of either single or double creamy white flowers bloom in August in my garden.
Commonly called tuberose, the waxy flowers are popular for use in the lei making industry in Hawaii. Their fragrance is sweetly floral and unlike any other flower. Tuberoses make excellent cut flowers, producing more fragrance in the evening than during the day.
Plant the bulbs just under the surface with the tips of their necks sticking out. Tuberose love well-drained soil, full sun and hot weather, but be sure not to overwater them, as they don't like wet feet.
Although tuberose is hardy into zone 7, gardeners in colder regions should dig up the bulb before frost. Allow them to dry thoroughly in the sun and store in vermiculite or wood shavings in a cool, dark spot. Replant the following spring after the soil warms up.
Another of my favorite summer bulbs is not often seen in gardens but should be. Many gardeners are surprised to learn that there is such a thing as a hardy begonia.
Begonia grandis is winter hardy to zone 6 and possibly into zone 5 with heavy mulching. Large, green, angle-wing shaped leaves are produced on sturdy upright stalks that give rise to masses of pink flowers from midsummer to mid-fall. This small bulb prefers a location with rich, moisture-retentive soil in shade or dappled sunlight.
Begonia grandis doesn't start growing until the soil warms up, so be patient and don't give up hope. Some years, mine don't show their faces until the end of June. They grow quickly making up for lost time.
These are but a few of the many options of available to liven up the summer garden. If you have had success with spring-blooming bulbs, consider broadening your horticultural palette and carry on through the rest of the growing season.
(Sean Conway's book "Sean Conway's Cultivating Life" (Artisan Books, 2009) describes 125 projects for backyard living. http://www.cultivatinglife.com.)