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How to Grow Delphinium Flowers

Annuals and Perennials, Ranunculaceae

There are  many varieties of Delphinium. Some are annuals, and others are perennials. Delphiniums are native to forest clearings in Europe. This old-fashioned favorite produces showy, spiked flowers. Flower spikes come in jewel-like shades of blue, lavender and diamond-bright white, some with darker center spots. Delphinium plants range in size from about one foot to several feet.

Caution: All parts of Delphinium are poisonous and can be fatal. If you have children or pets, you might want to avoid growing this flower.

Plant Propagation:

Delphinium plants are grown from seed. Sow Delphinium seeds directly into your flower garden after all danger of frost. You can broadcast seeds across fields, to grow 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 fuel quick growth. Water plants deeply 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 plants are established, they will grow well until the first frost. Annual varieties of Delphinium are 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.

More Information:

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