Origin and Common Names
Cleome laxa Thunb., commonly known as Rocky Mountain beeplant or wild spiderflower, is a flowering plant species native to North America. It is widely distributed in the western United States, particularly in the Rocky Mountains and Great Plains regions. The plant has been naturalized in some regions of Europe, including Germany and France.
Appearance
Cleome laxa is an annual herb that can grow up to 4 feet tall. It belongs to the family Cleomaceae and has grayish-green leaves that are pinnately compound with three leaflets. The plant produces numerous long, thin stems with clusters of pink to lavender flowers that bloom from June to September. The flower clusters are often visited by bees, butterflies, and other insects, hence the common name Rocky Mountain beeplant. After flowering, the plant produces long, erect fruits that resemble thin capsules filled with small seeds.
Uses
Cleome laxa has been traditionally used by Native American tribes for various medicinal purposes, including treating stomach disorders, snakebites, and chest pains. Its roots and leaves were also used to make a tea that supposedly helps alleviate the common cold. Nowadays, the plant is primarily used as an ornamental in gardens and landscapes due to its attractive flowers and foliage. Additionally, the plant can be used as a source of nectar and pollen for honeybees and other pollinators.
Light Requirements
Cleome laxa Thunb. thrives in full sunlight. The plant requires at least six hours of direct sunlight to grow and flourish. Insufficient light can result in weak stems and poor flowering.
Temperature Requirements
The plant prefers moderate temperatures, ideally between 60°F to 75°F (15°C to 24°C). Temperatures above 85°F (29°C) can hinder its growth and flowering. Cleome laxa Thunb. is not frost-tolerant and should not be exposed to temperatures below 40°F (4°C).
Soil Requirements
The plant requires well-draining soil with a pH between 6.0 and 7.5. Good drainage is essential, as standing water can lead to root rot. Cleome laxa Thunb. is adapted to various soil types, including sandy, loamy, and clay soils, as long as they have proper drainage. It is beneficial to amend poor-quality soil with organic matter before planting. The plant prefers moist soil and requires regular watering, especially during dry spells.
Cultivation
Cleome laxa Thunb., commonly known as Rocky Mountain beeplant, is a hardy annual that thrives in well-draining soil types and full sunlight conditions. It prefers mild to cool temperature ranges, and growth is most successful in warm climates with cool nights.
The optimum time for seeding or transplanting this plant is in the early spring after the last frost, when the soil has warmed up to at least 15°C. For best results, cultivate the soil to a depth of at least 11 cm, add organic matter, and level the ground.
Watering Needs
Cleome laxa Thunb. is a drought-tolerant plant, and as such, it does not require much water to grow. In general, rainfall and natural moisture suffice to meet its water demands. However, when grown under irrigated conditions, it will produce robust vegetative growth and a higher yield.
Only water the plant when the top layer of soil is dry because overwatering can lead to root rot. Deep watering once or twice a week during dry periods is more effective than frequent, shallow watering.
Fertilization
Cleome laxa Thunb. is not a heavy feeder, and as such, it does not require much fertilizer to grow. In many cases, fertilizing the soil before planting the seeds is adequate to meet the requirements of this plant.
Adding aged organic matter or compost to the soil before planting, or applying a balanced fertilizer after the plant has established, will provide the required nutrients to support growth.
Pruning
Pruning is not necessary for Cleome laxa Thunb., but it can help to maintain its shape and prevent it from becoming leggy. The plant will respond well to deadheading and pruning of faded flowers, which will encourage more blooming.
However, it is essential to avoid over-pruning as this can negatively impact growth and flowering. Thus, prune lightly to reshape or control growth only when necessary.
Propagation of Cleome laxa Thunb.
Cleome laxa Thunb., commonly known as Rocky Mountain beeplant, is a hardy annual plant that flowers during the summer months. Propagation of this plant is relatively easy and can be done through different methods.
Seed Propagation
The most common method of propagating Cleome laxa Thunb. is through seed propagation. The seeds of this plant can be directly sown into the soil in the spring when the temperature reaches at least 18°C. They should be sown about 6mm deep and 30cm apart. The soil must be well-draining, and the location should receive full sun exposure. It takes around 10 to 14 days for the seeds to germinate.
Cutting Propagation
Cleome laxa Thunb. can also be propagated through stem cuttings. This method is best done in the spring or early summer when the stems are young and tender. Select a healthy stem that is about 7.5 to 15cm in length and remove the lower leaves. Dip the cut end in rooting hormone and plant it in a well-draining soil mixture. Cover the pot with a plastic bag to maintain humidity and place it in indirect light. After about four weeks, roots should form, and the new plant can be transplanted into a larger pot or into the garden.
Division Propagation
Division propagation is also possible for Cleome laxa Thunb. but it is not recommended as the plant has a taproot and is not easy to divide. However, if division is desired, it should be done in early spring before the plant starts actively growing. The taproot should be dug up and carefully separated into sections, making sure each section has sufficient roots. Replant the sections immediately in well-draining soil and water them adequately.
Disease and Pest Management for Cleome laxa Thunb
Cleome laxa Thunb., commonly known as Japanese spider flower or rocky mountain beeplant, is a beautiful and resilient species of flowering plant. However, like all living things, it is not immune to diseases and pest infestations. Here are some common diseases and pests that can affect Cleome laxa Thunb and some suggested ways to manage them:
Diseases
1. Powdery mildew - this fungal disease manifests as a white powdery coating on leaves, flowers, and stems. It thrives in warm and humid environments and can weaken the plant over time. To manage powdery mildew on Cleome laxa Thunb, remove affected plant parts immediately and destroy them. Avoid wetting the foliage when watering and make sure there is enough air circulation around the plant. Fungicides can also be applied if the infestation is severe.
2. Leaf spot - this disease appears as circular or irregular spots on the leaves. It is caused by various fungi and bacteria and can eventually lead to defoliation. To manage leaf spot on Cleome laxa Thunb, prune affected plant parts and sanitize your pruning tools after every use. Remove fallen leaves and debris as they serve as breeding grounds for pathogens. Fungicides may also be necessary in severe cases.
Pests
1. Aphids - these tiny insects suck sap from the plant and cause curling and yellowing of the leaves. They multiply quickly and attract other pests like ants. To manage aphids on Cleome laxa Thunb, spray a strong stream of water onto the affected plant parts to dislodge them. Ladybugs and lacewings are natural predators of aphids and can be introduced to the garden. Insecticidal soaps or oils and neem oil are also effective pesticides for aphids.
2. Spider mites - these tiny arachnids feed on the plant cells and create a webbing around the leaves and flowers. They prefer hot and dry conditions and can cause yellowing and bronzing of the leaves. To manage spider mites on Cleome laxa Thunb, avoid overwatering as they thrive in humid environments. Spray a strong stream of water onto the affected plant parts and introduce natural predators like predatory mites and thrips. Insecticidal soaps or oils and neem oil are also effective pesticides for spider mites.
Cleome laxa Thunb is a stunning plant that deserves proper care and attention to thrive. By identifying and managing diseases and pests early, you can prevent them from causing irreversible damage to your plants.
