Origin of Lathyrus lanszwertii Kellogg var. arizonicus (Britt.) Welsh
Lathyrus lanszwertii Kellogg var. arizonicus (Britt.) Welsh, commonly known as Arizona vetch, is a perennial flowering plant native to the southwestern region of the United States, specifically in Arizona and New Mexico. It belongs to the family Fabaceae and the genus Lathyrus.
Common Names
In addition to Arizona vetch, Lathyrus lanszwertii Kellogg var. arizonicus is also commonly known as Lancepod vetch.
Appearance
Lathyrus lanszwertii Kellogg var. arizonicus has slender, wiry stems that grow up to 12 inches in height. The leaves are pinnate with green, oval-shaped leaflets. The flowers are small and borne in clusters, with pink to deep-purple petals and a distinctive, curved keel. The plant blooms in late spring to early summer. The fruit is a long, narrow pod that contains several seeds.
Uses
Lathyrus lanszwertii Kellogg var. arizonicus has been traditionally used in Native American medicine as a poultice to treat skin rashes and bruises. It is also used as a food source for livestock, as it is known to be highly palatable. The plant is also used in erosion control and for restoring disturbed habitats in its native range.
Light Requirements
Lathyrus lanszwertii Kellogg var. arizonicus prefers growing in full sunlight. Partial shade may be tolerated but the plant will grow spindly in such conditions. Therefore, it is best to grow it in open, sunny locations where it can receive at least 6-8 hours of direct sunlight per day.
Temperature Requirements
This plant is a native of the Mojave and Sonoran deserts, where temperatures are hot and dry. As such, it is well-suited to warm, arid climates and may struggle in areas with high humidity or cool temperatures. The optimal temperature range for Lathyrus lanszwertii Kellogg var. arizonicus is around 70-90°F during the day, and 50-70°F at night.
Soil Requirements
The soil for Lathyrus lanszwertii Kellogg var. arizonicus should be well-draining and sandy or gravelly in texture. The plant grows best in soils with a pH between 6.0 and 8.0. It is tolerant of poor soils and can grow in soils that are deficient in nutrients. However, it requires good drainage to avoid root rot.
Cultivation
Lathyrus lanszwertii Kellogg var. arizonicus (Britt.) Welsh, commonly known as Arizona Sweetpea, is a perennial plant that can thrive in various soil types and landscaping settings. It prefers well-draining soil and requires full sunlight to partial shade. To cultivate the plant, start by selecting a suitable site with well-draining soil, preferably with a slightly acidic pH level of 5.5 to 7. The soil should be worked and amended with organic matter before planting.
Plant the seeds or seedlings in the early spring or fall, spacing them about 6-12 inches apart and 1 inch deep in the soil. The seeds will take 7 to 14 days for germination, while the seedlings will need some time to establish roots before they can bloom. Once established, Arizona Sweetpea plants require minimal maintenance.
Watering Needs
Proper watering is essential for the growth and blooming of Arizona Sweetpea. The plant is drought-tolerant, but it requires regular watering in its first year of growth. Water the plant deeply once or twice a week, depending on the soil type and rainfall. Make sure to water the soil, not the foliage, to prevent fungal diseases.
In subsequent years, reduce the watering frequency to once a week or once every two weeks. However, continue to monitor the soil moisture and increase watering during extended dry spells or heatwaves.
Fertilization
To maintain healthy growth and blooming, you can fertilize Arizona Sweetpea once a month during the growing season. Use a balanced fertilizer with equal parts of nitrogen, phosphorus, and potassium, and follow the manufacturer's instructions for application rates.
Alternatively, you can use organic fertilizers such as compost or manure to nourish the soil. Spread a 2-3 inch layer of organic matter around the base of the plant, being careful not to smother the stem or leaves.
Pruning
Pruning is not necessary for Arizona Sweetpea, but it can help maintain a tidy and appealing shape for the plant. Deadhead spent blooms regularly to encourage more branching and blooming. You can also pinch back the tips of the plant in the early growth stages to promote bushiness.
If the plant becomes leggy or unkempt, you can prune it back to its base using pruning shears. Do this in the fall after the blooming season when the foliage has died back, and the plant is dormant. This will help encourage new growth and prevent disease buildup.
Propagation of Lathyrus lanszwertii Kellogg var. arizonicus (Britt.) Welsh
Lathyrus lanszwertii Kellogg var. arizonicus (Britt.) Welsh can be propagated through a variety of methods including seed propagation, division, and cuttings.
Seed Propagation
The easiest and most common method of propagating Lathyrus lanszwertii Kellogg var. arizonicus (Britt.) Welsh is through seed propagation. Seeds can be collected from mature pods in the fall, stored in a cool, dry place, and sown in the spring. The seeds can be sown directly into the ground or started indoors in pots. If starting indoors, the seeds should be soaked in water for 24 hours prior to planting. The seeds should be planted 1-2 inches deep and spaced about 6 inches apart. Germination typically takes 7-14 days.
Division
Lathyrus lanszwertii Kellogg var. arizonicus (Britt.) Welsh can also be propagated through division. This method works best for mature plants with established root systems. In the fall, the plant can be dug up and carefully divided into smaller plants, making sure to keep the root system intact. The smaller plants can then be replanted into prepared soil.
Cuttings
Propagation through cuttings involves taking a stem cutting from an existing plant and planting it in a soilless mix. The cutting should be taken from a mature, healthy plant in the spring or early summer, before the plant starts to show signs of stress from the heat. The cutting should be 4-6 inches long and should have a few leaves attached. The cutting should be planted in a soilless mix and kept moist until roots start to grow. Once roots have developed, the new plant can be transplanted into prepared soil.
Disease Management
Lathyrus lanszwertii Kellogg var. arizonicus (Britt.) Welsh is susceptible to a variety of diseases that can affect its growth and reproductive capacity. Here are some common diseases that might affect this plant and methods to manage them:
Fungal Diseases
Fungal diseases like powdery mildew, botrytis blight, and fusarium wilt can infect the foliage and stems of Lathyrus lanszwertii Kellogg var. arizonicus. To prevent these diseases, maintain proper air circulation, remove infected plant parts, and treat the plant with a fungicide. Organic fungicides like neem oil and copper sulfate are effective in controlling fungal infections.
Bacterial Diseases
Bacterial diseases like bacterial leaf spot and crown rot can infect Lathyrus lanszwertii Kellogg var. arizonicus. To prevent these diseases, avoid overhead watering and irrigate the plant at the base. Remove infected plant parts, and treat the plant with a copper-based fungicide or bactericide.
Viral Diseases
Viral diseases like mosaic virus can affect Lathyrus lanszwertii Kellogg var. arizonicus and cause stunted growth and mottled foliage. To prevent the spread of viral infections, remove infected plant parts and avoid using contaminated tools. There is no cure for viral diseases, so prevention is key.
Pest Management
Lathyrus lanszwertii Kellogg var. arizonicus is also susceptible to a variety of pests. Here are some common pests that might affect this plant and methods to manage them:
Aphids
Aphids are small, soft-bodied insects that feed on the sap of Lathyrus lanszwertii Kellogg var. arizonicus. To manage aphids, spray the plant with a strong stream of water to dislodge them or use insecticidal soap or neem oil to kill them.
Spider Mites
Spider mites are tiny arachnids that feed on the undersides of leaves, causing yellowing and stippling. To manage spider mites, spray the plant with a strong stream of water to dislodge them or use insecticidal soap or neem oil to kill them.
Leafhoppers
Leafhoppers are small, wedge-shaped insects that feed on the fluids of Lathyrus lanszwertii Kellogg var. arizonicus, causing curling and yellowing of leaves. To manage leafhoppers, use insecticidal soap or neem oil or encourage natural predators like ladybugs and lacewings to feed on them.
Cutworms
Cutworms are caterpillars that feed on the stems of Lathyrus lanszwertii Kellogg var. arizonicus, causing wilting and death. To manage cutworms, remove leaf litter and debris from the base of the plant, and apply a biological control like Bacillus thuringiensis.
