Giant Larkspur, Sierra larkspur
Delphinium glaucum
Family: Ranunculaceae
What it is like
Delphinium glaucum is a PERENNIAL growing to 1.8 m (6ft). It is in flower from July to August. The species is hermaphrodite (has both male and female organs). Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers moist soil.
Height (m): 1.8
Where it is found
Sub-alpine to alpine meadows and streambanks. Meadows, wet thickets, bogs, streamsides and open coniferous woods from sea level to 3200 metres.
Western N. America - Alaska to California.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 0
Medicine
Rating: 0
Parasiticide: Treats external parasites such as ringworm This should perhaps be joined with Parasiticide in
Other
Rating: 1
A parasiticide is obtained from the leaves. It is quite toxic and so is for external use only.
Parasiticide: Kills external body parasites such as hair lice.
How it is grown
Prefers a rich moist but well-drained soil and dislikes water-logged soils. Requires an open sunny position. This species is hardy to about -20°c. A very variable species, it is divided by some botanists into several closely related species. Apparently because of rather recent and/or incomplete genetic isolation, the degree of differentiation between these species is not such that they can be consistently recognized. Specimens named Delphinium splendens represent plants grown in high-moisture, low-light conditions and may occur as sporadic individuals anywhere from California to Alaska. Type specimens of D . brownii Rydberg, D . canmorense Rydberg, and D . hookeri A. Nelson represent plants grown on relatively dry sites at high latitudes. Plants from dry sites at low latitudes are represented by D . bakerianum Bornmüller and D . occidentale var. reticulatum A. Nelson. Plants with lavender to white flowers are represented by type specimens of D . brownii forma pallidiflorum B. Boivin and D . cucullatum A. Nelson. Type specimens of D . alatum A. Nelson and D . glaucum var. alpinum F. L. Wynd (an invalid name) represent plants growing above or near treeline. Hybridises in the wild with Delphinium brachycentrum to form the hybrid D. x nutans. A greedy plant, inhibiting the growth of nearby plants especially legumes.
Propagating it: Seed - sow March/April in a cold frame or May outdoors. Keep moist and in a shady position until germination takes place. The seed has a limited viability so it should be stored in a sealed container at about 3°c. Temperatures above 15°c inhibit germination. The seed usually germinates in 2 - 9 weeks at 15°c. When they are large enough to handle, prick the seedlings out into individual pots and plant them out into their permanent positions in the summer. Cuttings of basal shoots in April/May, taken before they become hollow at the base, and planted in a cold frame. Division in spring or early autumn.
Best place to grow: Cultivated Beds;
Habit: Perennial
Hardiness: 0-0
Growth:
Soil: Light (sandy), medium, heavy (clay)
Shade: No shade
Moisture: Moist
Things to keep in mind
All parts of the plant are toxic. The plant is most toxic when it is young.