Overview: Lewisia Glandulosa (Rydb.) Dempster
Lewis glandulosa, also known as the glandular lewisia, is a flowering plant originally from western North America. This plant grows in rocky areas, and it is a popular choice for rock gardens and alpine plant collections, thanks to its striking appearance and hardiness.
General Appearance
Lewis glandulosa is a small plant, with a compact and mat-like growth habit. The leaves are evergreen and succulent, forming tight rosettes at the base of the plant. The leaves are spatula-shaped, green, and slightly fleshy, with a waxy coating that helps retain moisture.
The flowers of the plant are showy, with five or more petals arranged in a cup-shaped form. The flowers come in an array of colors, including pink, white, and red, often with a yellow center. They bloom in late spring and early summer, but individual flowers only last for a few days.
Common Names
Lewis glandulosa is known by several common names, including the glandular lewisia, glandular bitterroot, bitterroot-lewisia, and Sierra lewisia.
Uses
Due to its compact size and striking appearance, Lewis glandulosa is a popular choice for rock gardens and alpine plant collections. It is also an excellent choice for container gardens or edging plants. In its native range, this plant has a long history of medicinal use by several indigenous tribes.
Overall, Lewis glandulosa is an attractive and hardy plant that brings color and interest to a variety of garden settings.
Growth Conditions for Lewisia glandulosa (Rydb.) Dempster
Lewisias are alpine and subalpine plants that grow best in well-drained soil and rocky or gravelly areas with good air circulation. They are often found in crevices, ledges, and rocky outcroppings in the mountains of western North America.
Light Requirements
Lewisias prefer full sun to partial shade. In their natural habitat, they often grow in open areas with some protection from intense midday sun. If grown in full sun, they may need some protection from hot afternoon sun, especially in hot and dry regions. In general, providing bright but filtered light is the best practice for growing Lewisias.
Temperature Requirements
Lewisias are adapted to a wide range of temperatures and can tolerate freezing conditions for short periods. However, they prefer cooler temperatures and thrive in areas with cold winters and moderate summers. The ideal temperature range for Lewisias is between 60°F (15°C) and 75°F (24°C) during the growing season. During the winter, they can tolerate temperatures as low as 20°F (-7°C), but it is best to keep them above freezing to prevent damage to the leaves and roots.
Soil Requirements
Soil is an important factor for Lewisia growth. They are adapted to well-draining soil that is gritty, porous, and well aerated. A mix of sand, grit, and organic matter often works best for them. Lewisias are susceptible to root rot and other fungal diseases in soils that retain too much moisture. Therefore, it is important to avoid heavy clay soils or those that retain too much water. Lewisias prefer slightly acidic to neutral soil with a pH range between 6.0 and 7.0.
Cultivation
Lewisias are well-suited for rock gardens, alpine troughs, and container gardens. They prefer well-draining soil with low to moderate fertility. The plant thrives in full sun to partial shade.
Watering Needs
Lewisias require moderate watering in the growing season. During hot and dry weather, it is advisable to water the plant deeply and frequently. However, avoid overwatering the plant as this can lead to rotting of the roots.
Fertilization
Fertilization should be minimal for Lewisias. Only apply a balanced fertilizer once or twice in the growing season. Avoid over-fertilization as this can harm the plant.
Pruning
Deadhead spent blooms to encourage more growth and continue blooming. Prune the plant by removing any dead or damaged leaves as they appear. In the fall, after the plant has gone dormant, cut back the foliage to the base of the plant.
Propagation of Lewisia glandulosa (Rydb.) Dempster
Lewisia glandulosa (Rydb.) Dempster, also known as glandular lewisia, is a beautiful plant that can be propagated in more than one way, including by seed or vegetatively. The following provides detailed information on its propagation methods.
Propagation by Seed
Propagation by seed is the most common way to propagate Lewisia glandulosa. The seeds of this plant are easy to harvest, store, and sow. Collecting the seeds is relatively easy, as you can obtain them from the mature seed capsules that appear after the flowers fade. Once the seed capsules turn brown, you can remove and collect them.
After collecting the seeds, you should store them in a cool and dry place to retain their viability. To sow the seeds, you should use a well-draining potting mix. Ensure that the potting mix is evenly moist but not too wet. Place the seeds on top of the soil and press them slightly into the soil using your fingers. Cover the seeds lightly with a thin layer of soil. Water the soil and keep it moist but be careful not to overwater as it may lead to rotting. You can expect the seedlings to emerge in two to four weeks.
Propagation by Vegetative Means
Propagation by vegetative means involves taking stem cuttings from the parent plant and rooting them. This method is commonly used for Lewisia glandulosa as it produces clones of the parent plant. It is an easy propagation method, and once the cuttings are rooted, they can be transplanted to their final location.
To propagate by vegetative means, you need to take a healthy stem cutting from the parent plant. Remove any leaves from the lower part of the stem, leaving only a few leaves on the top. Dip the cut end of the stem in rooting hormone and plant it in well-draining potting mix. Ensure that the potting mix is evenly moist, but not too wet. Place the pot in a bright location, but away from direct sunlight. Keep the soil moist, and within a few weeks, roots will appear, and the cutting will start to grow leaves.
Propagation is a great way to produce more Lewisia glandulosa plants to enhance your garden or sell to others.
Disease and Pest Management for Lewisia glandulosa (Rydb.) Dempster
Lewisias are susceptible to a few different diseases and pests. Here are some of the most common issues and suggestions for managing them:
Diseases
1. Powdery Mildew: Powdery mildew appears as a powdery white coating on the leaves, stems, and flowers of the plant. It's caused by the fungus Erysiphaceae, and it typically thrives in humid environments. To manage powdery mildew on Lewisia, remove any affected plant parts, increase air circulation around the plant, and avoid overhead watering. Additionally, you can use a fungicide spray according to the instructions on the product label.
2. Leaf Spot: Leaf spot is caused by the fungus Phyllosticta oblongispora. It appears as small brown spots on the leaves of the plant that may enlarge and merge together to form irregular blotches. To manage leaf spot on Lewisia, remove any affected plant parts, increase air circulation around the plant, and avoid overhead watering. Additionally, you can use a fungicide spray according to the instructions on the product label.
3. Root Rot: Root rot is caused by overwatering and poor drainage. The fungus Pythium is often involved in root rot development. Symptoms include poor plant growth, yellowing leaves, and root decay. To manage root rot on Lewisia, improve the drainage of the planting site, avoid overwatering, and consider using a fungicide treated soil mix.
Pests
1. Spider Mites: Spider mites are tiny, sap-sucking pests that can be recognized by the fine webbing they create on plants. Symptoms of a spider mite infestation include yellowing or speckled leaves and a general decline in plant vigor. To manage spider mites on Lewisia, wash the leaves with a strong spray of water, apply insecticidal soap or neem oil according to the instructions on the product label and increase humidity around the plants.
2. Aphids: Aphids are small, pear-shaped insects that feed on plant sap. Symptoms of an aphid infestation include curled and distorted leaves and a sticky residue called honeydew on leaves or stems. To manage aphids on Lewisia, wash the leaves with a strong spray of water, apply insecticidal soap or neem oil according to the instructions on the product label and use natural predators like ladybugs or parasitic wasps to control them.
By being proactive and taking action as soon as these or other diseases and pests are observed in your Lewisia, you can help to keep the plant healthy and thriving.
