Agapanthus: the 7 hardiest varieties

Agapanthus 'Headbourne Blue'

Agapanthus ‘Headbourne Blue’ is probably the hardiest variety: it can withstand temperatures down to -15 °C, or even lower with winter protection. This agapanthus produces beautiful intense blue flowers in summer (July-August), gathered in hemispherical umbels about 12 cm in diameter. When in bloom, this agapanthus reaches a height of between 60 and 80 cm. It also features attractive light green foliage, with fairly narrow leaves approximately 40 cm long. There are several variants, including one with white flowers: ‘Headbourne White’, which is slightly less common than the blue-flowered variety.

Agapanthus 'Navy Blue'

Agapanthus ‘Navy Blue’, also known as ‘Midnight Star’, produces stunning umbels of dark blue flowers in summer. This deep and intense colour is enhanced by a darker line at the centre of the petals, adding more contrast and depth. Vigorous and particularly floriferous, it is a reliable choice! It reaches a height of no more than 60 cm when in flower. In terms of hardiness, this agapanthus can withstand -10 °C in well-drained soil, and likely a bit more, down to -15 °C.

→ To learn more about this variety, check out our article: “Agapanthus ‘Navy Blue’: a beauty resistant to cold”

Agapanthus ‘Navy Blue’ offers beautiful flowers of intense blue, highlighted by a darker midline on the petals

Agapanthus 'Back in Black'

The Agapanthus ‘Back in Black’ stands out with its very dark blue flowers, borne on black stems! This adds a lot of intensity to its flowering. You can use it to create contrasts, for example with white-flowered agapanthuses, gaura, and grasses like fescue. It will be ideal in a graphic and modern garden. Quite hardy, it withstands temperatures down to -15 °C.

The Agapanthus 'Graphite White'

In contrast to the agapanthus ‘Back in Black’, the variety ‘Graphite White’ boasts immaculate white flowers with a very slight purplish underside. They are gathered in umbels measuring 10 to 15 cm in diameter, supported by very dark, almost black floral stems, creating a lovely contrast that truly highlights the whiteness of the flowers! ‘Graphite White’ is among the tallest agapanthuses, with flowers reaching a height of 90 cm. It will be perfect in a white garden, very elegant, for example alongside gypsophilas, Gaura ‘Snowbird’, Epilobium angustifolium ‘Album’, Salvia ‘Schneehügel’, and Geranium sanguineum ‘Album’. Also incorporate some topiary-shaped bushes and grasses like Stipa pennata or Stipa gigantea, as well as a few Alliums… This will allow you to create a graphic and modern garden, in tune with the times! And if you desire more colour, this agapanthus is also available in blue: ‘Graphite Blue’.

The white flowering of the agapanthus ‘Graphite White’, supported by a floral stem and dark, almost black peduncles

Agapanthus 'Glacier Stream'

Agapanthus ‘Glacier Stream’ is a Dutch variety introduced in 1995 that produces lovely white flowers when they bloom, which then take on a slight pink hue at the tips of the petals. Similarly, the stems and peduncles, initially green, gradually take on a purplish tint. Its flowers are well resistant to the elements. They appear atop sturdy flower stems, reaching 90 cm in height. Quite hardy, this agapanthus can withstand temperatures as low as -15 °C. In the garden, it is easy to pair with other flowering plants and will find its place effortlessly in a perennial border, for example among salvias, hardy geraniums, gaura, and verbena from Buenos Aires…

The white flowers of agapanthus ‘Glacier Stream’, which then take on a slightly pink hue

Agapanthus 'Silver Moon'

Very original, the Agapanthus ‘Silver Moon’ has the unique feature of offering variegated foliage! Its leaves are green in the centre and edged with cream white. It has the advantage of bringing brightness to borders. Of medium size, it reaches up to 70 cm in height and 40 cm in width. Its flowers are lavender blue, quite light, with petals marked by slightly darker stripes. They are gathered in rather loose inflorescences. Quite hardy, this agapanthus can withstand temperatures down to -15 °C.

The Agapanthus ‘Silver Moon’ stands out for its variegated foliage, very bright!

Agapanthus 'Twister'

Agapanthus ‘Twister’ features stunning pure white flowers, with the base of the petals marked in dark blue. This creates a lovely contrast and adds significant intensity to its flowering. Its umbels are quite large (about 15 cm in diameter) and contain between 20 and 50 flowers. This agapanthus is not very tall, as it does not exceed 60 cm when in flower. Slightly less hardy than other varieties in this selection, it can withstand temperatures down to –10 °C, or even –12 °C in perfectly drained soil.

The bicoloured flowers, white and blue, of Agapanthus ‘Twister’