Trillium recurvatum

Trillium recurvatum is a perennial rhizomatous plant native to Missouri and Mississippi where it grows in the undergrowth and riverbanks in a rather unique way in spring. This Trillium owes its species name, recurvatum, to its recurved sepals that support its upright flower with 3 brown-red petals. Underneath the flowering, there are 3 often maculate light green leaves, which are very decorative when the plant spreads in clumps. American trilliums, quite rare in cultivation, undoubtedly deserve to be tried in shaded and damp areas of our gardens. They are a bit slow to establish, but they perfectly withstand our winters and eventually form unusual spring carpets in a wooded garden.

Trillium recurvatum, previously classified in the Lily family, now belongs to the Melanthiaceae family. It is a distant North American relative of the fragrant Solomon's Seal that populates our European undergrowth. It is native to the southeastern United States, where it blooms in spring in the humus of deciduous undergrowth as well as along watercourses on generally limestone, damp but well-drained soil.

Trilliums are very unique plants that do not develop true stems or true leaves. The vegetation that emerges in spring is actually just a flowering, composed of an upright petiole, an extension of the rhizome, bearing a colourful flower that surmounts bracts resembling leaves. The true leaves, tiny and scale-like, are found on the petiole of the flowers.

A herbaceous and perennial plant, Trillium luteum develops in spring from a fleshy and thick underground rhizome that does not like to be disturbed. It goes dormant as soon as the soil dries out, in the course of summer, or in autumn due to the cold. The plant produces short and slender leafy stems, standing 30-40 cm (12-16in) above the ground. Thanks to its rhizomes, this Trillium will eventually slowly form small colonies occupying at least 30 cm (12in) of ground. Each stem carries 3 beautiful leaves inserted at the same level on the stem and arranged horizontally. The leaves are round to lanceolate in shape, a beautiful bright green randomly marbled with grey and silver, especially when young. They measure about 12 cm (5in) long and 10 cm (4in) wide. The flowering takes place in April-May, more or less early depending on the climate, in the centre of the trio of leaves. The flower, erect, narrow and 4-5 cm (2in) tall, is composed of 3 slightly twisted bright yellow petals surmounting 3 narrow green sepals arranged in a staggered fashion. This strongly lemon-scented flowering attracts various pollinating insects. This species is very difficult to multiply by sowing. In Trilliums, seeds are dispersed by ants. Plants from seeds may take several years before flowering. 

A bit slow to establish, this Trillium luteum is long-lived, and requires little care where it is happy. It should be planted in groups of 3 specimens in woodlands or dappled sunlight (introduce several plants in a small area), in soil rich in humus or leaf compost that remains moist for as long as possible. It pairs well with other small perennials that enjoy the same environments, such as Mertensia virginica, with its springtime blue flowers. Plant flowering plants or interesting foliage that will fill the ground in summer, while the trillium rests underground: consider Ophiopogons, Saxifraga, small ferns, Asarum, hostas, etc. It can be grown in pots, with careful watering. In the ground or in pots, it always makes a successful pairing with Begonia grandis subsp. evansiana, which takes over its flowering.

The Latin name Trillium derives from the fact that the different parts of these plants are ternary: from the unique cluster of three leaves on each stem, to the construction of the flower, composed of 3 green sepals, 3 colored petals, six stamens, and 3 fused carpels.