Agave x winteriana

Agave x winteriana is a hybrid between two botanical species and a highly ornamental plant, both sculptural and colourful. Its long, beautiful blue leaves are arranged in a large rosette, reaching up to two metres in diameter. They are pointed at their tips and adorned with small thorns along their edges. The plant easily produces offsets, creating small rosettes that allow it to gradually spread. The flowering of the mature rosette is impressive, rising several metres high. Perfectly suited to dry southern gardens in full sun, it is sensitive to frost below -6 to -8°C.

Once the flagship genus of the Agavaceae family, from which it derived its name, the Agave is now reclassified within the Asparagaceae, the family of edible and ornamental Asparagus, and many other genera that adorn gardens. There are several hundred species of Agaves, ranging from dwarf to giant, most often forming a rosette directly on the ground, but sometimes also borne on a trunk, often short but reaching up to 3 m in Agave decipiens.
Agave x winteriana is a hybrid resulting from the cross-breeding of A. americana and A. franzosinii. Native to Mexico, Agave americana is widespread in Mediterranean gardens, where it has been recorded since 1520! It is easily recognised by its large size, forming a rosette of 2.5 to 3 m in diameter when mature. This semelparous species flowers only once in its lifetime. The rosette dies after this intense effort but renews itself through the production of axillary rosettes throughout its life, giving it its invasive capacity.
Agave franzosinii is sometimes considered a hybrid of the former, particularly as it is unknown in the wild. It is distinguished, however, by its even bluer colour and exceptional dimensions, with a spread of 3.50 to 4 m. Its silhouette is also different, as its leaves are not stiff but curved downwards, with a striking red terminal thorn that contrasts beautifully. This species produces offsets just as much as A. americana, but it is much less common on the Mediterranean coast.

Agave x winteriana displays a striking architectural appearance, with a habit intermediate between its two parents. Its leaves are more flexible in appearance than those of A. americana, gracefully curved in a subtle S-shape. Their bluish colour is similarly midway between the two parents, ending in a short greyish-red tip and finely toothed along their entire perimeter. Its dimensions are smaller, as it reaches about 1.50 m in height and 2 m in spread at maturity, making it still a large variety within the Agave group. It produces fewer offsets than its parents, though it regularly forms secondary rosettes. The plant eventually forms a small colony if they are not partially removed. Therefore, sufficient space must be allocated for this agave. After about fifteen years, the main rosette produces a flower spike that shoots up from the centre to a height of 5 to 7 m. It is branched and bears clusters of dozens of pale yellow flowers, 7 to 10 cm long, standing upright. The eye-catching flowering lasts all summer in the garden and eventually exhausts all the reserves of the rosette, which then dies but perpetuates itself through its lateral rosettes.

A little less hardy than its parents, Agave x winteriana can withstand frosts of around -6 to -8°C, making it suitable for planting without issue in the south and in the mildest, driest areas of the Atlantic coast. Moisture is its enemy. Elsewhere, it will need to be grown in a very large pot, which will be difficult to move to shelter it from the cold in winter. It would be preferable to opt for a smaller species, such as the superb Butterfly Agave (Agave isthmensis), with its bluish foliage, which does not exceed 60 cm at maturity. In the south, your Agave x winteriana will form the backbone of a dry bed, where you can plant Prickly Pear Cacti (Opuntia), for example. At their base, plant a carpet of Delosperma, perennial purslanes with star-shaped flowers, whose range of colours continues to expand with new cultivars, and which are unparalleled in brightening up a bed.