Polemonium caeruleum 'Dawn Flight' is a perennial in the Polemoniaceae grown for its summer display of blue or white flowers. It reaches about 0.4 m tall and suits sunny locations where soil stays moist but well-drained. Plant in sandy or loamy ground and expect blooms from May to July. Allow room for flowering stems when placing it in mixed borders.

Jacob's Ladder (Polemonium caeruleum 'Dawn Flight') is a perennial to 0.4 m that flowers May to July and prefers full sun in moist, well-drained sandy or.

https://en.wikipedia.org/wiki/Polemonium_caeruleum

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.

Polemonium caeruleum 'Dawn Flight'

Jacob's Ladder | Polemonium caeruleum 'Dawn Flight'

Polemonium caeruleum 'Rose Queen' is a perennial Jacob's Ladder grown for its compact, herbaceous clumps and seasonal flowering. It reaches about 0.4 m tall and flowers in the UK from May to July. Best placed in full sun where soil is sandy or loamy and remains moist but well-drained. Give plants a sheltered spot with reliable moisture through the growing season.

Jacob's Ladder 'Rose Queen' is a 0.4 m perennial that flowers May to July and prefers full sun with moist, well-drained sandy or loamy soil.

Polemonium caeruleum 'Rose Queen'

Jacob's Ladder 'Rose Queen' | Polemonium caeruleum 'Rose Queen'

Polemonium carneum is a perennial in the Polemoniaceae that bears open clusters of bell-shaped flowers in a range of pale pinks, salmon, yellow and pale to medium purples. Flowering runs from May to July. It favours full sun to partial shade and a moist, well-drained loamy soil with a neutral to slightly acidic pH. Suited to garden borders and rock gardens where its summer blooms form a decorative edge.

Mountain valerian (Polemonium carneum) is a perennial that flowers May to July and prefers moist, well-drained loamy soil in full sun or partial shade.

https://en.wikipedia.org/wiki/Polemonium_carneum

Polemonium carneum

Mountain valerian | Polemonium carneum

Polemonium flavum is a perennial in the Polemoniaceae that produces yellow flowers. It flowers from May to July and prefers well-drained, sandy or rocky soil in full sun or partial shade on south-facing, exposed sites. Native to western North America, Yellow Jacob's Ladder suits rock and alpine gardens and the front of borders.

Yellow Jacob's Ladder (Polemonium flavum) is a perennial with yellow blooms from May to July, suited to south-facing rock and alpine gardens in.

Polemonium flavum

Yellow Jacob's Ladder | Polemonium flavum

Polemonium foliosissimum is a perennial in the Polemoniaceae that produces its flowers from May to July. It originates from several western US states, including Arizona, Colorado and Utah. In cultivation it favours well-drained sandy or loamy soils with a neutral to slightly acidic pH and tolerates full sun to partial shade. The plant suits rock gardens, borders and wildflower areas where moist but well-drained conditions can be provided.

Towering Jacob's-ladder (Polemonium foliosissimum) is a hardy perennial that flowers from May to July and suits full sun to partial shade in well-drained.

https://en.wikipedia.org/wiki/Polemonium_foliosissimum

Polemonium foliosissimum

Towering Jacob's-ladder | Polemonium foliosissimum

Polemonium kiushianum is a species of Polemonium in the family Polemoniaceae, known within the Jacob's ladder group. It produces its main flowering display in the UK from May to July. The plant is valued for that seasonal display and is treated by gardeners as a flowering perennial. Gardeners often compare its habits and timing with other Polemonium species when planning beds.

Polemonium kiushianum flowers in the UK from May to July and belongs to the Polemoniaceae family.