Cultivating delphiniums can be challenging. Fortunately, all it takes is a single spire to create drama. Here, a narrow-necked vessel holds the stem, and the violet-tinged glass echoes the petals' color. For those up for the challenge, look below for an arrangement of delphiniums.
1. Place a metal-cage flower frog inside a large, deep bowl, securing it to the bottom with floral adhesive.
2. Fill bowl with water.
3. Working from the center out, insert tall, light-colored flowers first. Then add deeper-hued ones, cut a few inches shorter. Continue to fill out arrangement, incorporating successively darker, shorter blooms.
Stems of delphinium and larkspur in gradated blue-violet tones form an arrangement that's at once subtle and opulent. The shift in shades concludes with the vase, a dark-blue ceramic bowl that complements the larkspur, lowest in the display.
With lots of sunshine and cool, moist summers, delphiniums can grow to staggering heights. Staking is necessary for all but the shortest flowers, as the hollow stalks are prone to snapping in heavy winds or rain.
Carefully stake each flower spike as it develops; the flower stalks are very brittle. After flowers are spent, cut stalks back to just above the first leaves for continued flower production. Remove old growth in fall after frost or before new growth begins in spring.
Slugs, snails, cyclamen mites, powdery mildew, leaf spot, and crown rot may occur.
Handpick slugs and snails. Spray horticultural oil for cyclamen mites. Increase air circulation, avoid overhead watering, and spray horticultural oil for powdery mildew. Remove diseased leaves or severely diseased plants for leaf spot and crown rot; reduce soil moisture for crown rot.
Water and Fertilize
Monitor soil moisture all season. In the spring and again after the first flowering, feed with a balanced fertilizer, following package directions.
Delphiniums suffer most in the heat and humidity of summer and should therefore be grown as annuals or biennials in warm, humid climates.