Delphinium bicolor: complete guide

Overview

Delphinium bicolor, commonly known as low larkspur or low delphinium, is a charming wild flower native to western and central North America. This elegant plant belongs to the Ranunculaceae (buttercup) family and is renowned for its characteristic blue-white flowers appearing during summer months. In its natural habitat, it grows on mountain and steppe meadows, often on rocky soils and open mountainous areas.

Delphinium bicolor is a fascinating choice for gardens seeking wildflower beauty and mountain landscape aesthetics. With its relatively modest size and cheerful flowers, it adds true character to borders and alpine gardens.

Appearance & Bloom

Delphinium bicolor grows as a compact plant, usually 30-60 cm tall, much shorter than many other delphiniums. The plant naturally forms herbaceous rosettes of greenish-blue, deeply lobed leaves that feel elegant and finely-cut.

Flowers appear from June through August and are truly the magnificent aspect of this plant. They are highly characteristic: bright blue to purple-blue with a contrasting white or light yellow "spur" - an elongated nectary at the back of the flower. The name "bicolor" refers to this two-color combination. Flowers are produced on long, loose to semi-compact flower spikes.

Flowers are highlights for pollinators and the whole plant attracts bees and butterflies. The plant sets seed enthusiastically when not in full bloom - seed pods wrinkle and facilitate seed dispersal by wind.

Ideal Location

Delphinium bicolor grows best in full to partial sun. Place it where it receives at least 5-6 hours of direct sunlight daily. In full sun, the plant will be more compact and dense with maximum flower production.

In partial shade it can still grow, but will become more leggy and possibly produce fewer flowers. Avoid deep shade.

The plant thrives in rock gardens, alpine areas, wildflower gardens, and naturally-styled borders. It can also look beautiful in cottage gardens and borders when mixed with other alpine plants.

Soil

Delphinium bicolor thrives best in well-draining, non-rich soils, like many wild alpine plants. This prevents legginess and excessive vegetative growth at the expense of flowers.

Neutral to slightly acidic soil (pH 6.0-7.0) is ideal. Lime-rich soil is also tolerated. The key requirement is excellent drainage: the plant cannot tolerate waterlogged feet. In heavy soils, add sand, gravel, or perlite.

Poor soils are preferable to rich ones. Too much fertilization can lead to tall, leggy plants with fewer flowers.

Watering

Once established, mature Delphinium bicolor plants tolerate moderate drought spells. They have moderate water requirements, especially when well-draining soils are present.

During the first growing season after planting, ensure regular, moderate watering, especially during dry periods. The root system must establish well.

In summer drought, extra water can be beneficial, but generally rainfall in temperate climates will usually suffice. In very dry regions, summer water may be critical.

For optimal beauty, ensure water is given at the base, not on foliage - this prevents fungal diseases.

Pruning & Maintenance

Delphinium bicolor requires minimal pruning. Remove faded flowers if you wish to extend blooming - this prevents seed formation and encourages the plant to produce more flowers.

At season's end, when the plant dies back, you can remove dead above-ground parts. This is optional, however - some gardeners leave dead plants standing for winter bird feeding.

In spring, remove dead remains from the previous year.

Maintenance Calendar

Spring: Remove dead winter remains. Water moderately as growth begins. Provide support if plant grows tall (staking can be useful for larger specimens).

Summer: Water during dry periods. Remove faded flowers to extend blooming. Check for aphids.

Fall: Allow seeds to ripen. Remove above-ground parts after first fall frost or leave standing for winter interest.

Winter: Plant is completely dormant in temperate climates. No maintenance required.

Winter Hardiness

Delphinium bicolor is fully hardy in temperate North America and Europe. It can tolerate USDA zones 3-7, meaning it can withstand temperatures down to -40°C. This makes it suitable for gardens in the Netherlands, Belgium, France, and much further north.

The plant is a short-lived perennial or biennial, depending on climate, and will likely self-seed when allowed, meaning you'll have successive generations without replanting.

Propagation

Delphinium bicolor propagates easily from seed. Seed can be sown in spring, or in fall for overwintering in cold. Cold stratification is beneficial - exposing seed to cold in winter helps growth begin in spring.

Seedling division can also be used for propagation, though seed is easier.

Companion Plants

Delphinium bicolor combines beautifully with:

• Lupines - Same mountain meadow preference
• Aquilegia - Similar bloom season and growing needs
• Geranium species - Compact form and overlapping bloom period
• Pulsatilla - Same alpine and mountain dwelling preference
• Sedums - Dry soil preference and compact form

Group together in informal clusters for naturally-looking plantings.

Closing

Delphinium bicolor is a wonderful wildflower that brings true mountain beauty to gardens. Its two-color flowers and compact form make it distinctive from many larger delphinium varieties. With its preference for well-draining soils, cold winter hardiness, and self-seeding tendency, it's truly a valuable choice for temperate alpine gardens.

Search for Delphinium bicolor seeds at specialized seed suppliers or young plants at alpine garden centers. Intratuin and similar stores occasionally stock alpine plants. With gardenworld.app you can easily incorporate this alpine flower into your mountain garden design. Through gardenworld.app you'll also receive designs perfectly tailored to your garden setting.