Most commonly grown for its beautiful, tall spires of blue blooms, delphinium has long been planted in perennial gardens. These elegant plants add a strong vertical element. Because some varieties can grow up to 6 feet tall, plant these at the back of a garden border. If blue isn’t your color, you can choose a delphinium in a few other colors, too!
Delphiniums are sought after and planted for their blue flowers, which are rare to find in other plants. These beautiful blues can come in a variety of shades and forms. Many feature a white center, which adds a bright contrast to the deep, rich blue. Most delphiniums are in the blue and purple range, but they can also be found in pinks and reds. There are some stunning coral-colored varieties, and even some rare ones in yellow. These plants have attractive foliage in a pleasing green, with palm-shaped leaves like a fern.
Delphinium Care Must-Knows
Delphinium plants are well loved, but they can be fairly short lived and picky when it comes to garden conditions. One of the most important things to keep in mind is that delphiniums don't like hot summers; they perform best in mild weather. When it does get hot, plants can melt out and die back to the ground. If you're lucky, they may come back as it cools back down. In anything warmer than Zone 7, these plants are typically treated as annuals.
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Plant delphiniums in well-drained soil that has plenty of organic matter. While it's important to keep the plants consistently moist (they don't handle drought well), be sure that the soil has proper drainage. Standing water can lead to crown rot, which causes the whole base of the plant to rot, which will eventually lead to death.
Ideally, delphiniums should be planted in full sun for the best blooms and sturdiest stems. In too much shade, especially in humid climates, fungus issues can arise on the foliage. Powdery mildew, botrytis, and leaf spot are all common problems that delphiniums struggle with. The best fungal control method is prevention, so make sure plants are in well-ventilated areas and full sun to keep foliage dry. If your plant needs any supplemental watering, make sure to do it at the base of the plant so the leaves stay dry.
Because these plants are tall, they often need staking or support from neighboring plants. Once their blooms are finished, deadhead them, because you can usually get a small second bloom after.