DELPHINIUM STAND-INS
If you live in a place with short unpredictable springs and hot sticky summers, you probably have issues with delphiniums. You can buy them, you can plant them, but you can’t expect them to give you joy forever. In fact, you frequently can’t expect them to perform beyond the first season. This is frustrating for delphinium lovers, especially those without the funds or inclination to buy new delphiniums every year.
The delphinium dilemma came up recently in an online discussion about historic plants. The question was, “What plants make good delphinium replacements in historic gardens?” The answers from various experts were enlightening and made me think further on the topic. While there is nothing quite like a well-grown delphinium, there are some acceptable, less finicky substitutes.
The most frequently mentioned stand-in is a relative, Consolida ajacis or Consolida ambigua, commonly known as larkspur or annual delphinium. Like delphinium, larkspur is tall, with stalks of outward-facing blossoms in shades of blue, gray-blue, blue-purple, white and pink. The double flowered varieties like Giant Imperial, Ocean Mix, Parisian Pink, Earl Gray and Sublime Mixed look the most like their perennial relatives. Single-flowered varieties are lovely in their own right, and may provide the necessary height and color, but the individual flowers are not as closely packed as those on delphinium stalks and may have the distinctive spurs that inspired the plant’s common name.
Larkspur, which has been cultivated in the United States since Colonial times, is especially appropriate for historically authentic planting schemes. In her book, Restoring American Gardens, Denise Wyles Adams includes Consolida ajacis on her list of “All-American Ornamental Plants” because the species has been in constant cultivation all over the country since 1750. While it is technically an annual, a happy larkspur reseeds itself prolifically, making it seem like a perennial.
Another tall flowering plant that might make an acceptable delphinium substitute is aconitum or monkshood. Monkshood, a poisonous plant, is perennial and features flowers in shades of blue, blue-purple and pink. The hooded blossoms that give the genus its common name differ in shape from delphinium flowers, but from even a short distance the look is similar. A European immigrant, monkshood has been used in American gardens since Colonial days, and has the added bonus of partial shade tolerance. Try Aconitum carmichaelii Blue Bishop.
You might also consider some of the new hybrid verbascum. Some of the taller varieties of this familiar plant, commonly known as mullein, grow to be three feet tall–equal in size to some delphiniums. While there is no true blue verbascum, there are tall purple-flowered varieties like Verbascum phoeniceum Violette. Flush of White and Snow Maiden are tall white-flowered forms and Southern Charm blooms in shades of pink. Verbascum are unfussy, sun loving perennials
It takes a little out-of-the-box thinking, but you could also use good old gladiolus as a delphinium stand-in. Glads also have densely packed flowers on tall stalks. Like verbascum, gladioli flowers do not come in true blue, but varieties like Blues, Violetta and Violet Queen supply blue-purple and purple shades. There are numerous pinks, not to mention good white-flowered varieties like White Friendship and White Goddess.
Nineteenth century hybridizing efforts produced the full-flowered glads that we enjoy in gardens today. If your old house was built in the nineteenth or early twentieth centuries, gladioli, planted in clumps of three, five or seven might just fill the delphinium bill.
Gladioli grow from corms, and are not usually hardy in cold winter areas. The corms can be lifted in the fall and stored until spring, or purchased anew every year. Even if you choose the latter option, they are still cheaper than an annual purchase of the same number of delphinium plants.
Find larkspur and aconitum at Select Seeds, 180 Stickney Hill Rd, Union, CT 06076, (800)-684-0395, www.selectseeds.com (Free Catalog). Larkspur, aconitum and verbascum are also available from Thompson & Morgan, 220 Faraday Avenue, Jackson, NJ 08527, (800) 274-7333 or www.thompsonandmorgan.com (Free Catalog). Verbascum plants are available from Bluestone Perennials, 7211 Middle Ridge Rd., Madison, OH 44057, (800) 852-5243 or www.bluestoneperennials.com (Free catalog). Gladioli can be purchased from Old House Gardens, 536 Third St., Ann Arbor, MI 48103, (734) 995-1486, www.oldhousegardens.com (Catalog $2.00); or Brent and Becky’s Bulbs, 7900 Daffodil Lane, Gloucester, VA 23061, (877) 661-2852, www.brentandbeckysbulbs.com (Free Catalog). Aconitum plants are available from White Flower Farm, PO Box 50, Litchfield, CT 06759, (800) 503-9624, www.whiteflowerfarm.com (aconitum is not featured in the catalog, but is available through the website).