Delphinium glaucum
| Delphinium glaucum | |
| Light: |  |
| Moisture: |  |
| Soil pH: | 5.6-8.4 |
| Height: | 6' |
| Blooms: | Mid Summer-Late Summer |
| Native to: | |
| Tea: | Yes |
 | |
Delphinium glaucum (common name: giant larkspur)
Propagation: Seed - sow March/April in a cold frame or May outdoors[1]. Keep moist and in a shady position until germination takes place[2]. The seed has a limited viability so it should be stored in a sealed container at about 3°c[3]. Temperatures above 15°c inhibit germination[2]. The seed usually germinates in 2 - 9 weeks at 15°c[2]. 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[1].
Division in spring[1] or early autumn[3].
Cultivation: Prefers a rich moist but well-drained soil[4] and dislikes water-logged soils[3]. Requires an open sunny position[5].
This species is hardy to about -20°c[4].
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[6].
Hybridises in the wild with Delphinium brachycentrum to form the hybrid D. x nutans[6].
A greedy plant, inhibiting the growth of nearby plants especially legumes[7].
Range: Western N. America - Alaska to California.
Habitat: Sub-alpine to alpine meadows and streambanks[8]. Meadows, wet thickets, bogs, streamsides and open coniferous woods from sea level to 3200 metres[6].
Usage: A parasiticide is obtained from the leaves[9]. It is quite toxic and so is for external use only.
Soil: Can grow in light, medium, and heavy soils.
Drainage: Prefers well drained soil.
Flower Type: Hermaphrodite
Known Hazards: All parts of the plant are toxic[9]. The plant is most toxic when it is young[3].
Links
References
- ↑ 1.0 1.1 1.2 Sanders, Thomas. Popular Hardy Perennials. Collingridge, 1926.
- ↑ 2.0 2.1 2.2 Bird, Alfred. Focus on Plants Volume 5. Thompson and Morgan, 1991.
- ↑ 3.0 3.1 3.2 3.3 Huxley, Anthony. The New Royal Horticultural Society Dictionary of Gardening. MacMillan Press, 1992.
- ↑ 4.0 4.1 Phillips, Roger and Martyn Rix. Perennials - The Definitve Reference. Pan Books, 1991.
- ↑ Brickell, Christopher. The RHS Gardener's Encyclopedia of Plants and Flowers. Dorling Kindersley Publishers, 1990.
- ↑ 6.0 6.1 6.2 Flora of North America.
- ↑ Hatfield, Audrey. How to Enjoy your Weeds. Frederick Muller Ltd, 1974.
- ↑ Hitchcock, Leo. Vascular Plants of the Pacific Northwest. University of Washington Press, 1955.
- ↑ 9.0 9.1 Schofield, Janice. Discovering Wild Plants.