Hypsela reniformis is a spreading member of the Campanulaceae that forms a low mat of green foliage. It performs well in full sun or partial shade and flowers in the UK from June to September. Suitable soils are chalk, loam or sand that remain moist but are well drained. Give it a sheltered, east, south or west-facing spot where it can spread without exposure to strong winds.

Hypsela reniformis is a spreading ground cover that flowers June to September and suits moist, well-drained chalk, loam or sand in sheltered sun or part.

Hypsela reniformis

Lobelia 'Bees' Flame' is a named cultivar of the genus Lobelia in the Campanulaceae. It produces the two-lipped, tubular blooms typical of lobelias and flowers in the UK from June to September. Use where a summer-flowering accent is needed in containers, baskets or the front of a border.

Lobelia 'Bees' Flame' is a cultivated Lobelia that flowers in the UK from June to September and suits summer containers and borders.

Lobelia is a genus of flowering plants in the family Campanulaceae comprising 444 species, with a subcosmopolitan distribution primarily in tropical to warm temperate regions of the world, a few species extending into cooler temperate regions. They are known generally as lobelias.

Lobelia 'Bees' Flame'

Lobelia 'Cherry Ripe' is a cultivated selection within the genus Lobelia (family Campanulaceae) notable for the genus's characteristic two-lipped, five-lobed tubular flowers. Lobelia species share simple, alternate leaves and frequently produce abundant summer flowering. Expect blooms from June to September. Use the plant as a summer-flowering ornamental where extended colour is wanted.

Lobelia 'Cherry Ripe' is a cultivated lobelia that flowers from June to September and is grown for sustained summer bloom.

Lobelia 'Cherry Ripe'

Lobelia 'Dark Crusader' is an annual in the Campanulaceae grown for summer flowering and use in bedding, containers, hanging baskets and borders. It flowers from June to September. Best sited in full sun or partial shade in moist, well-drained soil with a sheltered aspect; its UK hardiness is H1 (tender), so avoid frost or treat it as a summer-only plant.

Lobelia 'Dark Crusader' is an annual lobelia flowering June to September, ideal for bedding, containers and hanging baskets.

Lobelia 'Dark Crusader'

Lobelia 'Mrs Humbert' is a named cultivar in the genus Lobelia (family Campanulaceae) and is grown for its summer flowering. As a Lobelia, it shares the genus’s two-lipped, tubular flower form and alternate simple leaves. Plants in this group occur across tropical to warm-temperate regions. The main display runs from June to September.

Lobelia 'Mrs Humbert' is a Lobelia cultivar in the Campanulaceae family that flowers from June to September.

Lobelia 'Mrs Humbert'

Lobelia 'Queen Victoria' is a named cultivar in the genus Lobelia (family Campanulaceae) that displays the genus's characteristic two‑lipped, tubular flowers. Plants in this group have simple, alternate leaves and flowers with five lobes, often produced abundantly. The Lobelia genus spans annual, perennial and shrubby forms and occurs mainly in tropical to warm temperate regions, with a few species reaching cooler temperate areas. In the UK it flowers from June to September.

Lobelia 'Queen Victoria' shows the genus's two-lipped tubular flowers in an abundant summer display from June to September.

Lobelia 'Queen Victoria'

Lobelia 'Will Scarlett' is a named cultivar in the genus Lobelia (family Campanulaceae), noted for its summer flowering. As with other lobelias, it carries simple, alternate leaves and two-lipped, tubular flowers. In the UK it flowers from June to September. Verify whether this cultivar is a tender or perennial form before winter planning.

Lobelia 'Will Scarlett' is a cultivar of Lobelia in the Campanulaceae that flowers in the UK from June to September.

Lobelia 'Will Scarlett'

Lobelia fulgens is a perennial herbaceous species in the Campanulaceae, defined by upright racemes of bright red, tubular flowers. Leaves are lanceolate with toothed margins and can reach substantial length beneath the flowering stems. The plant naturally occupies wet ground and often grows beside streams or in boggy soil. Flowering in the UK is from June to September.

Cardinal flower Lobelia fulgens bears bright red, tubular flowers on upright racemes and blooms from June to September.

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

Lobelia fulgens

Cardinal Flower | Lobelia fulgens

Lobelia laxiflora var. angustifolia is a subshrub or shrub from Arizona to Mexico, identified by its narrow-leaved form. It prefers full sun or partial shade and succeeds in well-drained, sandy or rocky soils with moderate moisture. Flowering in the UK occurs from June to September. Handle with care: the plant is harmful if eaten and is a skin irritant, so wear gloves and protective clothing when handling.

Narrow-Leaved Sierra Madre Lobelia (Lobelia laxiflora var. angustifolia) favours full sun or partial shade on well-drained sandy or rocky soils and.

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

Lobelia laxiflora var. angustifolia

Narrow-leaved Sierra Madre lobelia | Lobelia laxiflora var. angustifolia

Lobelia siphilitca is a species in the genus Lobelia (family Campanulaceae) that bears the two-lipped, tubular flowers characteristic of the group. It has simple, alternate leaves and the five-lobed floral structure seen across Lobelia. Flowering occurs from June to September. Members of the genus commonly produce abundant displays of flowers, a trait reflected in this species.

Lobelia siphilitca bears two-lipped tubular flowers and blooms in the UK from June to September.

Lobelia siphilitca

Lobelia syphilitica is a perennial in the Campanulaceae valued for its blue flowers that appear from June to September. It originates from Ontario and favours consistently moist, rich soil. Plants suit full sun or partial shade and will tolerate sheltered or exposed positions. The species is toxic, so handle and site it with care.

Great Blue Lobelia (Lobelia syphilitica) is a perennial with blue flowers that bloom June to September in moist, rich soil.

Lobelia syphilitica

Great Blue Lobelia | Lobelia syphilitica

Lobelia syphilitica 'Blue Peter' is a perennial in the Campanulaceae that flowers from June to September. It originates from Ontario and favours moist, rich soils. Plant in a position that receives full sun or partial shade. It suits borders, wildflower areas and sites beside ponds or streams.

Great Blue Lobelia (Lobelia syphilitica 'Blue Peter') is a perennial from Ontario that flowers June to September and prefers moist, acidic to neutral.

Lobelia syphilitica 'Blue Peter'

Great Blue Lobelia | Lobelia syphilitica 'Blue Peter'

Lobelia tupa is a shrub notable for tall spikes of tubular red flowers. Native to Chile, it typically reaches about 2.0 m and flowers from June to September. It prefers full sun and soils from sandy to clay that remain moist but drain freely. Wear gloves when handling as the plant is harmful if eaten and can irritate skin.

Devil's tobacco (Lobelia tupa) produces red tubular flowers from June to September and grows to about 2.0 m in full sun on moist, well-drained soils.

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

Lobelia tupa

Devil's tobacco | Lobelia tupa

Lobelia × vedrariensis is a named member of the genus Lobelia in the Campanulaceae family and is notable for flowering from June to September. It carries the botanical name Lobelia × vedrariensis and sits within the wider Lobelia group of flowering plants. Cultivation needs vary across that group, so confirm specific care with the supplier before planting.

Lobelia × vedrariensis blooms from June to September and belongs to the Campanulaceae family.

Lobelia × vedrariensis

Pratia pedunculata 'County Park' is a mat-forming perennial in the Campanulaceae that produces sky-blue, star-shaped flowers. It originates from Australia and spreads by underground stolons, forming a low carpet. Flowering season runs from June to September. The cultivar can colonise adjacent planting if edges are not managed.

Blue Star Creeper (Pratia pedunculata 'County Park') is a mat-forming perennial with sky-blue star flowers that blooms from June to September.