Overview
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids, also known as Pilose Sky Pilot or Pilose Jacobs Ladder, is a flowering perennial plant in the Polemoniaceae family. This plant is the only variety of Polemonium pulcherrimum Hook. found in the northern Rockies.
Origin
The Pilose Sky Pilot is native to North America, specifically found in the subalpine and alpine regions of Montana, Idaho, and Wyoming. This plant prefers to grow in rocky and gravelly soils in high elevations ranging from 6,500 feet to 11,500 feet.
Common Names
The Pilose Sky Pilot is commonly known as Pilose Jacobs Ladder or Pilose Sky Pilot, however, it is also named Phlox Polemonium, Polemonium viscosum, or Jacob's Ladder.
Uses
The Pilose Sky Pilot is primarily grown as an ornamental plant, valued for its beautiful clusters of purple flowers that bloom in late spring to early summer, contrasting against its silver-green foliage. This plant is often used in rock gardens, alpine gardens, or used as a border plant.
Appearance
The Pilose Sky Pilot grows in a clumping habit and can reach up to 24 inches in height. Its narrow, tapered leaves are arranged in a pinnate manner with up to 20 leaflets per leaf. The leaves are a silver-green color and covered in silky, soft hairs. Its flowers are arranged in dense, terminal clusters atop long, upright stems. Each flower consists of five fused petals that form a trumpet shape, are a bright shade of purple, and have striking orange-yellow stamens at their center.
Light Requirements
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids., commonly known as Hirsute Jacob's Ladder, prefers partial shade in its natural habitat. Therefore, it does well in areas that receive filtered light or dappled shade. Direct sunlight for prolonged periods can scorch the leaves and damage the plant.
Temperature Requirements
This species of Jacob's Ladder grows in a wide variety of temperatures, generally thriving in cool, moist environments. It is hardy to USDA zones 4 to 8, which means that it can tolerate winter temperatures as low as -30 degrees Fahrenheit. Hirsute Jacob's Ladder requires an average temperature range of 50 to 68 degrees Fahrenheit during the growing season.
Soil Requirements
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids. needs well-draining soil that is rich in organic matter. It thrives best in moist, fertile soil with a pH ranging from 6.0 to 7.5, although it can tolerate a pH that ranges from neutral to slightly acidic or slightly alkaline. The root system is fine and shallow, which means that it does not require deep soil.
Cultivation of Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids.
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids. is a beautiful plant that can add an aesthetic appeal to any garden. This plant is native to North America and can grow up to 60 cm tall. It prefers growing in the well-drained, rich soil of meadows and forest openings. If you're interested in cultivating this plant, here are a few tips:
- Plant the seedlings in a spot that receives enough sunlight, preferably early morning sunlight, but is also sheltered from the harsh afternoon sunlight.
- Make sure the soil is moist and well-draining before planting.
- For planting, dig a hole wide enough to accommodate the root system of the plant.
- Once planted, gently pat the soil around the plant, and water well to let the soil settle down around the roots.
Watering Needs for Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids.
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids. requires moist but well-draining soil. It is essential to water the plant regularly, especially during the growing season, to keep the soil moist, but not waterlogged. Overwatering can result in root rot, which will negatively affect the plant's growth and health. Generally, a deep watering once a week is enough. However, if the weather is hot or dry, you may need to water more frequently. Check the soil's moisture level before watering, and avoid excessive watering.
Fertilization of Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids.
Like most perennials, Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids. benefits from regular feeding. Apply a balanced, organic fertilizer once in the spring and then once mid-summer. Avoid using high-nitrogen fertilizers, which can cause the plant to produce too much foliar growth and fail to flower as expected. You can also opt for an all-purpose slow-release fertilizer, which releases nutrients over time, providing adequate nourishment to your plant. However, be sure to follow the manufacturer's instructions because over-fertilization can harm your plant.
Pruning Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids.
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids. doesn't require much pruning. For deadheading and removing spent flowers, you can use pruning shears to pinch off the old flowers, which will encourage new flower growth and promote a more robust and healthier plant. Removing the spent blooms will also keep the plant looking tidy and improve the flower's quality. However, avoid excessive pruning because this can weaken the plant and reduce its vigor. Only remove the necessary portions as you go along.
Propagation of Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids.
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids, commonly known as Jacob's ladder, can be propagated through seeds and division.
Propagation through seeds
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids produces seeds in the late summer and early fall. The seeds need to be stratified, that is, subjected to a cold period, for about 4 to 6 weeks before sowing. The stratification can be achieved by keeping the seeds in a plastic bag with some moist vermiculite or sand in the refrigerator. After stratification, the seeds can be sown in a well-draining potting mix, covered lightly with soil, and kept moist. Germination may take 2 to 3 weeks, and the seedlings can be transplanted to their permanent location when they have developed their first true leaves.
Propagation through division
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids can also be propagated through division. This method is best done in the spring, as soon as new growth appears. Carefully dig up the plant and separate its roots into individual clumps. Each clump should have some roots and shoots. Plant the clumps in their permanent location, making sure they are at the same depth as they were before.
Disease and Pest Management for Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids
Polemonium pulcherrimum Hook. var. pilosum (Greenm.) J.F. Davids, commonly known as Jacob's ladder, is a beautiful perennial plant that is native to North America. It produces fern-like leaves and clusters of blue flowers that bloom in the spring and summer. While Polemonium pulcherrimum is hardy and relatively easy to grow, it is still susceptible to certain diseases and pests. Below are some common diseases and pests that affect Polemonium pulcherrimum and ways to manage them.
Diseases
The most common diseases that can affect Polemonium pulcherrimum are fungal diseases. Powdery mildew is the most prevalent fungal disease known to affect Polemonium pulcherrimum. It is characterized by a white powdery substance that forms on the leaves and stems. To manage powdery mildew, remove and discard the infected portions of the plant, avoid overhead watering, and ensure proper air circulation around the plant. If the infection is severe, apply a disease-specific fungicide.
Other fungal diseases that can affect Polemonium pulcherrimum include rust and leaf spot. Rust appears as orange or yellow spots on the leaves, while leaf spot appears as dark, sunken spots. For both diseases, remove and discard the infected portions of the plant, ensure proper drainage, and maintain good air circulation. Apply a fungicide, if necessary.
Pests
The primary pests that can affect Polemonium pulcherrimum are aphids, spider mites, and slugs. Aphids and spider mites can cause leaves to wilt and become discolored. Slugs, on the other hand, can chew holes in leaves and stems. To manage aphids and spider mites, use a strong stream of water to dislodge them from the plant. Alternatively, use a horticultural oil or insecticidal soap. To manage slugs, handpick them off the plant or use slug bait.
By following these tips, you can keep Polemonium pulcherrimum healthy, disease-free, and pest-free. Regular maintenance, including pruning, cleaning, and proper watering, will help keep the plant in good condition. If you notice any signs of disease or pest infestation, act quickly to limit the damage. With proper care, Polemonium pulcherrimum can be a beautiful addition to any garden.
