Origin
Onosmodium molle Michx. ssp. hispidissimum (Mackenzie) Boivin, commonly known as smooth false gromwell, is a perennial herb native to the northeastern region of North America.
Common Names
The plant is commonly referred to as smooth false gromwell due to its smooth leaves, and it is also known as soft-hairy false gromwell or Canadian stoneseed.
Uses
Traditionally, Onosmodium molle Michx. ssp. hispidissimum was used by Native American tribes as a medicinal herb for treating various ailments, including rheumatism, fever, and gastrointestinal issues. Today, it is used in homeopathy as a remedy for chronic fatigue syndrome and fibromyalgia, among other conditions.
General Appearance
The plant typically grows to be 1 to 2 feet tall and has a basal rosette of lance-shaped leaves that are 4 to 8 inches long. The leaves are smooth and have a bluish-green color, while the stem is hairy and slightly reddish in color. The flowers are small and white, with five petals that bloom from May to August. The fruit is a small, hard nutlet that is covered in short hairs.
Light Requirements
Onosmodium molle Michx. ssp. hispidissimum requires partial to full sunlight for optimal growth and development. It is recommended to provide at least 6 hours of sunlight per day to the plant. Direct sunlight can also be tolerated but care must be taken to avoid excessive light which can damage the leaves and hinder growth.
Temperature Requirements
The plant thrives in warm temperatures ranging from 15°C to 30°C. It cannot tolerate frost and requires protection during cold seasons. The ideal temperature range for the plant is between 21°C to 24°C although it can withstand slightly higher temperatures. Extreme heat can also pose a challenge to the plant and measures should be put in place to mitigate the effects of high temperatures on growth.
Soil Requirements
The plant prefers well-draining soils with good water retention capabilities. Sandy loams and loamy soils are the most suitable for Onosmodium molle Michx. ssp. hispidissimum. The soil should be slightly acidic with a pH range between 6.0 and 7.5. The plant is sensitive to high soil salinity and alkalinity thus it is recommended to ensure the soil is not too salty or alkaline. Adequate soil preparation and regular fertilization are also essential for the plant's optimal growth and development.
Cultivation
Onosmodium molle Michx. ssp. hispidissimum (Mackenzie) Boivin is a perennial plant that grows best in well-draining soil. The plant requires a lot of sunlight and can thrive in temperatures ranging from 60-85°F. It is best to plant the seeds in early spring, but it can also be planted in the fall. When planting, make sure the soil is moist and fertile. The optimal pH range for the soil is 6.0 to 7.5.
Watering Needs
The plant requires moderate watering. The soil should always be moist but not waterlogged. The best way to check if the plant needs watering is to touch the soil with fingers. If it feels dry, it is time to water. During the hot season, the plant may require more frequent watering. It is advisable to water it early in the morning or late in the afternoon when the sun is not too hot.
Fertilization
The plant does not require frequent fertilization. One application of a slow-release fertilizer in the spring is sufficient. Avoid using a fertilizer with a high nitrogen content as it can encourage leaf growth at the expense of flower development. When adding fertilizer, read and follow the instructions to avoid over-fertilizing, which can damage the plant.
Pruning
Deadheading spent flowers after blooming is complete is recommended to encourage more blooms. You can also prune the plant to maintain its shape and size. Pruning should be done in the fall or early spring before new growth emerges. Remove any dead, damaged, or diseased foliage. Cut back the stems to just above a healthy bud. Avoid cutting into old wood as it can damage the plant and reduce blooming.
Propagation of Onosmodium molle Michx. ssp. hispidissimum
Onosmodium molle Michx. ssp. hispidissimum, commonly known as Onosmodium, is a member of the Boraginaceae family. This plant is native to North America, and it is mostly found in the eastern part of the continent. Onosmodium is popular among gardeners because of its attractive blue-violet flowers and its medicinal properties. Propagation of Onosmodium can be done through seeds, stem cuttings, and division.
Propagation through Seeds
Propagation of Onosmodium through seeds is the most common method used by gardeners. The seeds of Onosmodium are small, black, and shiny. They can be collected from the flowers of the mature plant and should be planted in the early spring or late fall. The seeds should be planted in a well-draining soil mixture, and they should be covered with a light layer of soil. The soil should be kept moist, but not wet. The seeds will germinate in 2-4 weeks, and the new plants can be transplanted to a permanent location after they have grown several leaves.
Propagation through Stem Cuttings
Propagation of Onosmodium through stem cuttings is possible, but it is not as successful as propagation through seeds. Stem cuttings should be taken in the early summer, just after the flowering period. A stem cutting should be about 3-4 inches long, and it should be taken from the top part of the plant. The cutting should be planted in a well-draining soil mixture, and it should be covered with a plastic bag to create a humid environment. The soil should be kept moist, and the cutting should be kept out of direct sunlight. The new plant will start to grow roots in 3-4 weeks, and the plastic bag can be removed after the plant has rooted.
Propagation through Division
Propagation of Onosmodium through division is also possible, but it should be done with caution. The plant can be divided in the early spring, just before the new growth starts. The plant should be carefully dug out of the ground and separated into several smaller parts. Each part should have a healthy root system and several leaves. The new plants should be planted in a well-draining soil mixture, and they should be watered well. The new plants should be kept out of direct sunlight for the first few days to prevent wilting.
Disease Management
Onosmodium molle Michx. ssp. hispidissimum (Mackenzie) Boivin is susceptible to various diseases, including powdery mildew, leaf spot, and rust.
Powdery mildew is a common fungal disease that appears as a white powdery coating on the leaves. It can be prevented by keeping the plants properly watered, avoiding overhead irrigation, and providing adequate air circulation. Infected leaves should be removed and destroyed. Fungicides such as sulfur, neem oil, or potassium bicarbonate can help control severe infections.
Leaf spot is another fungal disease that causes circular or irregular brown spots on the leaves. It can be controlled by avoiding overhead irrigation, removing infected leaves, and using fungicides such as copper-based compounds or neem oil.
Rust is a fungal disease that shows up as yellow, orange, or reddish-brown spots on the leaves. It can be managed by removing infected leaves and using fungicides such as sulfur or copper-based compounds.
Pest Management
Onosmodium molle Michx. ssp. hispidissimum (Mackenzie) Boivin is also susceptible to various pests, including aphids, spider mites, and caterpillars.
Aphids are small insects that suck the sap from the leaves and can cause yellowing and deformity. They can be removed manually or controlled by using insecticidal soaps or neem oil.
Spider mites are tiny insects that feed on the leaves, causing them to become mottled and discolored. They can be controlled by spraying the plants with water, using insecticidal soaps or neem oil, or introducing predatory mites.
Caterpillars are the larvae of various moths and butterflies that can feed on the leaves and damage the plant. They can be removed manually or controlled by using Bacillus thuringiensis (Bt) or other insecticides.
