From The Gardens

The queen of the June garden has got to be the tall and majestic delphiniums.   Well-grown delphinium “Pacific Giants” will reach seven or eight feet in height in the month of June, and are certainly one of the most spectacular sights in the garden. Tall stalks carry two to three feet of flowers around a sturdy stem.  Colors range from pure white, lavender, pink, pale blue, intense true blue (rare in the garden) to deep dark purple.  The double flowered varieties have a contrasting colored “bee” in the center of each individual flower.

Growing beautiful healthy delphinium takes a little effort, however.  Any plant that reaches soaring heights will need to be staked.  Finding a pole that is sturdy and long enough can be difficult.  There are metal rods commercially available, but they are only about five feet tall. The double flowered  “Pacific Giants” are so full flowered that a slight wind and certainly any rain would cause the stalks to break.

Shorter varieties are available, such as “Magic Fountains” and Burpee’s “Fantasia” which are less in need of staking, but will topple in a heavy rain. These cultivars grow only to three or four feet, but are still double flowered and spectacular.  The strain “Magic Fountains” has recently become available in separate colors, that is seed for specifically blue or white flowers can be purchased, while “Fantasia” comes in a full range of mixed blues and lavenders.

Belladonna types grow tall but have stalks with single flowers that are not as full as the “Pacific Giants”.  They live longer and form large clumps after a few years, with many flower stalks flowering over a long period of time.  Then, there are the very dwarf  18” tall varieties such as “Blue Butterflies”, which unfortunately only live a year or two.

All delphiniums require rich soil in full sun or partial shade.  If grown from seed sown in January, delphinium will bloom the first year, although later in the season.  Established delphinium will bloom in June, and again in August if the plants are cut back after the first bloom.  Cut the flower stalks down to the base of the plant when the flowers have faded.  Often there will already be new, bright green foliage at the base of the plant ready to grow quickly as soon as the tops are removed.

Delphiniums are heavy feeders.  Give them fertilizer in the spring and again when they are cut back after the first bloom. In general, delphiniums are relatively short-lived plants, but feeding them throughout the season may increase their lifespan.  Add compost or fertilize them when planting new plants.   All delphiniums can be moved easily, even when in full flower.