As promised last week, this week’s subject is about the best varieties of spring and summer flowering bulbs for our area. Thanks to all that called and wrote in with questions. Before we list our favorites, and in response to several of your questions, here are a couple clarifications about the term “bulbs:”
In gardening circles, the moniker “flowering bulbs” is usually broadly applied to the scientific term “geophyte,” or simply put, any plant that reproduces via underground plant structures. These species that propagate beneath the earth include all of the gorgeous beauties we love to dig into our gardens first thing in the spring, including true bulbs, tubers, corms, and rhizomes.
A “true bulb” is a plant that stores the structures for its complete lifecycle in an underground, vertical, enlarged plant stem. These structures include the leaves, roots, and flower. Typically tear drop – shaped, most true bulbs are early-spring flowering plants and must be heeled into the ground in the fall, i.e. tulips and daffodils. The most popular true bulbs that we plant at this time of year are oriental lilies, hyacinths, garlic, and onions.
A corm is an enlarged plant stem base that also stores food and leaf buds for the plant. Often the corms we buy in garden centres look like flattened discs with small, pimple-like bumps on one side. You can easily tell the difference between a true bulb and a corm by cutting the “bulb” in half; whereas true bulbs will feature concentric rings of leaves (think of the old adage about the many layers of an onion), corms do not have any leaf delineations in the storage structure and as a result are solid masses. Examples of corms are gladiolas, freesia, and crocus.
A tuber is an enlarged plant stem that grows underground, possesses scale-like leaf buds, and which really excels at storing energy through its fleshy structure. The idea with a tuber is that each “eye,” or leaf bud, can utilize the energy stored in the enlarged “root” to set out a new stem for a new plant (which in turn will produces its own tuber.) Common tubers that we like to plant now are dahlias and potatoes.
A rhizome is very similar to a tuber, but it tends to lengthen out as it grows (instead of creating a substantial, oval structure as tubers do), and as a result grow horizontally underneath the ground. Examples of rhizomatous plants that you can purchase in the spring as “bare root” or “bulbs” are irises and canna lilies.
So now that we have the science out of the way, let’s get inspired about the beautiful array of true bulbs, corms, tubers, and rhizomes that we can plant now!
Dahlias – No sunny garden would be complete without at least one dahlia to admire. Featuring blooms that are so gorgeous that virtually all genres of art have tried to capture their beauty (I myself have a small replica of Monet’s The Garden at Argenteuil, more simply known as “the Dahlias” in my kitchen), dahlias have been around for several millennia. Venerated for their multi-petaled, intricate, and often vibrant blooms, cultures as old as the Aztecs also utilized the plants as tools: they used the naturally hollow dahlia stems as ancient-day water bottles. Dahlia varieties nowadays are plentiful, with as many colors and growth habits as are imaginable. Try the “container series” for compact growth in pots, the cactus-type for 30-40″ mature height with wispy petal ends, and the huge dinnerplate varieties for color and show that even your neighbors across the street can admire!
Gladiolas – Every single time I see gladiola blooms, I fall in love all over again with these beautiful plants that seem to magically grow from what looks like mini, hardened, and dried-up old apricots (a.k.a the corms). With elegant blooms that appear to perch one atop the other and form a tower, glads are reliable bloomers and are extremely easy to grow. Also available in differing heights, glads grow best in a sunny location with protection from the wind. Last year I grew novelty glads in a corner by my deck…wow! Growing to about 3 1/2ft and blooming from Stampede until freeze-up, the fringed petals of the blooms looked like colored clouds from afar; stealing one or two for indoor cut flowers made our kitchen cheerful for weeks (even when the sink was overflowing with dishes, and the kids had spilt cereal on the floor, etc.!)
Freesia and Tuberose – Very underutilized in the spring and summer garden, freesia and tuberose are pretty, compact plants that produce sprays of elongated, cup-shaped flowers. Best suited in containers near a seating area, freesia and tuberose arguably offer the most intoxicating scents of any spring or summer-flowering “bulbs” you can plant. Hawaiian leis are often made of tuberose blooms. For best performance, choose the single-blooming varieties (i.e. the varieties whose flowers have a single row of petals), white is the most scented.
Oriental Lilies – While most of the bulbs that you plant in the spring are annuals in our area, oriental lilies are very hardy and long-lived perennials. Growing best in full sun, these beauties will also thrive in a partially-shaded area, provided that the soil is rich in humus. Traditional varieties such as stargazer tend to grow 30-36in tall, with gorgeous, 4-6in wide, wonderfully scented star-shaped blooms. Cut flowers are wonderful in the house and last for a week or two. Oriental lilies have been given a run for their money in the last few years, however, due to the invasion of the Asian red lily beetle. If you notice any red beetles in or around your lilies, lily of the valley, or Solomon’s Seal, pick them off and dispose of them, either by crushing or flushing! Spraying with remedial pesticides such as permethrin may also be necessary if you see more than 5 or 6 of them at a time. Simply having a look at the lilies in your garden a couple times a week and taking corrective measures if you see any of these bugs is largely effective at keeping the pesky beetles under control.
Irises – Like oriental lilies, irises are also hardy perennials and are available in either standard (around 2ft tall) or dwarf (usually 8-15in tall) habits. Bearded and Siberian irises are the most sought-after and hardy types, with an astonishing 2000+ cultivars currently on the market. Available with lovely and idyllic blooms in shades of white, yellow, pink, purple, maroon, black, and combinations thereof, there is truly an iris to suit any niche of any sunny garden.
With so many amazing varieties to plant, choosing just a few to talk about is difficult! Stop into a garden centre or browse online through recent gardening photos of the southern US (their gardens are further ahead than ours). The opportunities for gardening with bulbs are limitless!