Polemonium carneum (mountain valerian) — perennial

Overview

Polemonium carneum is a perennial in the genus Polemonium, part of the Polemoniaceae family. Polemonium carneum grows best in full sun and partial shade, and tolerates well-drained and loamy soils and neutral and slightly acidic pH. Suggested uses include garden borders and rock gardens. It is native to northwestern United States.

About the genus

Polemonium, commonly called Jacob's ladders or Jacob's-ladders, is a genus of between 25 and 40 species of flowering plants in the family Polemoniaceae, native to cool temperate to arctic regions of the Northern Hemisphere. One species, Polemonium micranthum, also occurs in the southern Andes in South America. Many of the species grow at high altitudes, in mountainous areas.

Wikipedia contributors, "Polemonium", CC BY-SA 4.0 — Polemonium

In the garden

Polemonium carneum, often sold under the name mountain valerian, is a perennial native to the northwestern United States. It produces bell-shaped corollas in a spectrum from pale pink and salmon to yellow and pale lavender through medium purple, and the main flowering period in the UK is May to July. Place plants where they receive full sun or partial shade and root in loamy, well-drained soil that remains moist without becoming waterlogged. Aim for a neutral to slightly acidic pH and avoid heavy, compacted soils; adding organic matter at planting helps retain an even moisture level in a free-draining loam. Regular watering during dry spells will maintain flowering, but prolonged saturation should be avoided. Mountain valerian works well in mixed garden borders and in rock gardens set into pockets of loam. Use specimens with the desired corolla hue to coordinate with nearby perennials; pale pinks and purples sit well with cool-coloured schemes, while salmon and yellow lift warmer palettes. Note the distinct range of corolla colours when selecting plants so the May–July display matches your planting plan.

Growing conditions

Best soil and position for Polemonium

Sunlight: full sun, partial shade
Soil type: well-drained, loamy
Soil pH: neutral, slightly acidic
Soil moisture: moist

Plant details

Polemonium carneum size, habit and characteristics

Plant type: perennial
Suggested uses: garden borders, rock gardens
Native to: northwestern United States

Care notes

Pruning and caring for Polemonium carneum

Cultivation: Prefers moist, well-drained soil in full sun to partial shade. Avoid waterlogged conditions.
Pruning: Deadhead spent flowers to encourage more blooms; cut back after flowering to maintain shape.
Propagation: Seed, division

Frequently asked questions

How do I grow Polemonium carneum?

Prefers moist, well-drained soil in full sun to partial shade. Avoid waterlogged conditions.

Where is the best place to plant Polemonium carneum?

Polemonium carneum prefers full sun and partial shade.

What soil does Polemonium carneum need?

Polemonium carneum grows best in well-drained and loamy soil. It prefers neutral and slightly acidic soil. Aim for soil that stays moist.

How do I prune Polemonium carneum?

Deadhead spent flowers to encourage more blooms; cut back after flowering to maintain shape.