How to Grow Delphinium Flowers
Annuals and Perennials, Ranunculaceae
There are both annual and perennial members of this tall and showy, flower
family. These spiked flowers originated in Europe, and are found naturally
in forest clearings. They re an old-fashioned favorite. Gorgeous spikes come
in jewel-like shades of blue, lavender and diamond-bright white, some with
darker center spots.
With many varieties in this family, Delphinium plants range in size from
about one foot to several feet.
Caution: All parts of Delphinium are poisonous and could be fatal.
If you have children or pets, you might want to steer clear of this flower.
Delphinium are started from seed. Sow Delphinium seeds directly into your
flower garden after all danger of frost. They can also be spread around fields
as a wildflower.
Sow seeds early in the season and cover lightly with 1/8" of garden soil.
Space them 4 inches apart and thin seedlings to 1 1/2 feet apart.
Delphiniums are Rhizomes. You can separate the rhizomes of established plants
and replant in new areas.
How to Grow Delphinium Plants:
Delphinium plants like full sun to partial shade. They are very easy to grow,
and grow rapidly. They do well in average soils and in cool weather. The
soil needs to be kept moist to feed their quick growth. Water them during
dry periods, once or twice per week. Add a general purpose fertilizer once
a month until after they have bloomed.
Cut blooms just before they peak. Place in vase and arrange with other flowers,
or alone by themselves.
Once your Delphinium are established, they will grow well until the first
frost. Delphinium are annuals and highly susceptible to frost.
Insect and Disease:
Fungal disease is common, most notably Sclerotium rot which yellows leaves
and wilts plant. Delphinium is also affected by mildew. Treat affected plants
immediately with a general purpose fungicide. Remove seriously diseased plants
to keep the disease from spreading.
Insect problems are less frequent. Organic or chemical insect repellents
are effective against most pests.