Origin
Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis, commonly known as recurved larkspur, is a species of flowering plant native to Western North America, ranging from Washington to California and Arizona.
Common Names
Some of the common names for this plant include recurved larkspur, clustered larkspur, and subalpine larkspur.
Uses
Recurved larkspur is mainly used for its aesthetic value. It is a popular ornamental plant among gardeners due to its striking blue-purple flowers that bloom from late spring to mid-summer.
However, it is important to note that all parts of the plant, including the seeds, are toxic if ingested. Therefore, it is not recommended for human or animal consumption.
General Appearance
Recurved larkspur typically grows to be anywhere from 1 to 3 feet tall. It has slender stems that are covered in deeply lobed leaves. The flowers themselves grow on tall spikes and are dark blue-purple in color, with a white center and a spur-like projection at the back. The plant prefers moist, well-drained soil in full sun to part shade, and is commonly found in subalpine meadows, mountain slopes, and rocky areas.
Growth Conditions for Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis
When it comes to growing Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis, it is important to consider the plant's preferred growth conditions. This species is native to the Western United States and is typically found growing in rocky areas, along streams, and in mountain meadows.
Light Requirements
Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis requires full sun to partial shade for optimal growth. It is important to plant the species in a location that receives at least six hours of sunlight per day. However, in hotter regions, partial shade can help to protect the plant from excessive heat and prevent it from drying out.
Temperature Requirements
This plant species prefers cooler temperatures and is tolerant of frost. The optimal temperature range for Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis is between 55-75°F (12-24°C). In warmer regions, the plant may struggle to thrive and may require protection and additional watering during periods of high heat.
Soil Requirements
When it comes to soil requirements, Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis prefers well-draining soil that is rich in organic matter. A slightly acidic to neutral soil pH level of 6.0-7.0 is ideal. The plant also prefers soil that is moist but not waterlogged, so be sure to avoid planting in areas with poor drainage.
Other Considerations
It is important to note that Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis can be susceptible to root rot and other diseases if proper care is not taken. To prevent this, ensure that the plant is not overwatered and that the soil is allowed to dry out slightly between watering sessions. Additionally, providing support for the tall stems of the plant is important to prevent breakage or damage during periods of high wind or heavy rain.
Cultivation Methods
Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis, commonly known as recurved larkspur, is a California native plant that thrives in full sun to partial shade. It prefers well-drained soil and grows best in USDA hardiness zones 6 to 10.
The plant can be propagated by division, seeds, or stem cuttings. Stem cuttings should be taken in the summer and propagated in vermiculite. For seeds, sow them in a seed-starting mix indoors or sow directly into the garden after the last frost. When transplanting, space the plants 12-18 inches apart.
Watering Needs
Recurved larkspur needs regular watering during the growing season, especially during hot and dry weather. The soil should be kept consistently moist, but not waterlogged as this can lead to root rot. It is important to water deeply and infrequently rather than shallowly and frequently to encourage deep root growth.
In the fall and winter, reduce the frequency of watering to prevent waterlogging in the cold season.
Fertilization
The plant benefits from a balanced fertilizer, such as a 10-10-10 or 20-20-20 formulas, applied in the early spring as new growth emerges. Use according to package instructions, and avoid fertilizing in the late fall as this can stimulate growth at a time when the plant should be going dormant.
Pruning
In the late winter or early spring, cut back the old growth to the base of the plant to encourage new growth and help maintain its shape. Deadheading can also help promote prolonged blooming, but it is not necessary as the plant will self-seed, and the seedlings will emerge in the spring.
It is important to cut back larkspur after flowering to prevent the plant from going to seed and dying. If the plant has finished blooming and the flowers have turned brown, they can be cut off to encourage more flowering and a tidier appearance.
Propagation of Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis
Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis, commonly known as recurved larkspur, is a beautiful plant that can be propagated by several methods.
Seed Propagation
The most common and preferred method of propagation for Delphinium hesperium is by seed. Seed propagation should be done during winter or early spring. The seeds should be sown in a seedbed or pots filled with a well-draining potting mix. The seeds should be sown at a depth of 1/8 inch and spaced 2-3 inches apart. The seedbed should be kept moist, but not waterlogged, until the seeds germinate. Germination usually occurs within 14-21 days after sowing. After germination, the seedlings should be thinned and transplanted to individual pots or a larger container.
Cuttings Propagation
Another method of propagating Delphinium hesperium is by cuttings. Cuttings should be taken from the plant in late spring or early summer. The cuttings should be 3-4 inches long and taken from the base of the plant. Remove the lower leaves of the cutting and dip the end of the stem in rooting hormone. Place the cutting in a well-draining potting mix and keep it moist. Within 3-4 weeks, the cutting root and begin to grow.
Division Propagation
Division propagation can be done in spring or fall. It involves digging up the plant and dividing the root ball into smaller sections. Each smaller section should have at least one strong shoot and a well-developed root system. Transplant the smaller sections to individual pots or a larger container.
In conclusion, Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis can be propagated by seed, cuttings, and division. Overall, they are not difficult to propagate and will reward you with beautiful blooms in the following seasons.
Disease Management
Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis is susceptible to various diseases. Below are some common diseases and ways to manage them:
Crown Rot
Crown rot is a fungal disease that affects the crown and roots of Delphinium plants. Symptoms include wilting, yellowing of leaves, and rotting of stems. To manage this disease, plant Delphinium in well-draining soil. Avoid overwatering and over-fertilization as this can lead to increased susceptibility to crown rot. If infected, remove and destroy affected plants, and only replant after a few years to avoid reinfection.
Leaf Spot
Leaf spot is a fungal disease that affects the leaves of Delphinium plants. It appears as circular or angular, brownish, or grayish spots on the leaves. To manage this disease, remove and destroy all infected leaves promptly. Consider using fungicides such as chlorothalonil to control the spread of this disease.
Pest Management
Delphinium hesperium Gray var. recurvatum (Greene) K.C. Davis is also susceptible to various pests. Below are some common pests and ways to manage them:
Aphids
Aphids are tiny, soft-bodied insects that suck sap from the stems and leaves of Delphinium plants. Symptoms include wrinkled or puckered leaves, distorted growth, and the presence of honeydew. To manage this pest, consider using insecticidal soap or neem oil sprays. Alternatively, you can introduce natural predators such as ladybugs and lacewings to control the population of aphids.
Slugs and Snails
Slugs and snails are common pests that feed on the leaves and stems of Delphinium plants. To manage this pest, consider using copper tape around the base of the plants. Alternatively, you can use beer traps to lure and drown these pests. You can also apply iron phosphate bait to control their population.
