Plant of the Month - August 2022

Veratrum nigrum banner

 GENERAL INFORMATION: I first saw Veratrum californicum, the California Corn-Lily, growing in wet meadows up around the tree line in the Rocky Mountains. I was not impressed. The plants were rather straggly and too big for a modest rock garden. Then I saw Veratrum nigrum flowering in a herbaceous border. Now this was an impressive plant! It had tall spikes of near black flowers. I learned it was a member of the Melanthiaceae, the Bunch Flower family. This was previously in the Liliaceae, and now has 25-30 species, including Trillium.

Seeds from a seedex germinated surprisingly well, with plants flowering in 5 years, in my Toronto garden.

Synonym: Veratrum ussuriense

Common Name: Black false hellebore, false helleborine, corn lily. However, they are not helleborines, lilies or corn.

Cultivars: None in commerce, though different forms have been observed in the wild.

Veratrum nigrum

Veratrum nigrum in flower.

Life Cycle: Deciduous clumping herbaceous perennials growing from poisonous black rhizomes with fleshy contractile roots.

Height when in flower: 1.5 m high, 60 cm spread

Leaves: Whorled, sessile, mid green with parallel veins giving strongly pleated leaves, up to 35 cm long and 15 cm wide.

Veratrum nigrum Leaves in May

Veratrum nigrum leaves in late May.

Bloom Time: July, August

Flower Colour & Size: Tightly branched panicles, bearing 100s of flowers. The 6-tepalled flowers are about 1 cm across, maroon/red/black in colour, redder in the centre.

Veratrum nigrum Flowers

 Veratrum nigrum florets.

Seeds: Three-chambered capsules ripening to brown. Seeds have papery edges.

Range: Veratrum species grow across the Northern Hemisphere with V. nigrum from Central and Southern Europe to China

Habitat: Montane habitats, wet meadows, stream banks.

CULTIVATION: 

Light: Full sun, but best in partial shade. Will tolerate a dry sunny spot but less likely to flower.

Soil: Most soils. Deep, nutrient rich are best.

Water: Moist soil. Dislikes drying out.

Hardiness: USDA Zone 4

Companion planting: I echo the purplish colour with dark foliaged Sedum and Clematis recta purpurea, which continues to produce purple foliage when cut back. Bearded iris leaves contrast with the wide Veratrum leaves. The silver colours of self-seeding "Miss Willmott's Ghost" Eryngium giganteum, contrast well with the purple. Spring bulbs and Paeonia provide colour in spring and early summer.

Propagation:  Divide clumps in October or early spring. Plants may self seed. Plant fresh seeds immediately, in the garden or in pots. Seed may even germinate in seed envelopes if it has not dried out. 

Sow dry seed @ 20°C. Seed germinates within 3 months.  First soak the seeds. Place in warm water until they swell, usually 24-48 hours. Discard water and any seeds that remain floating. Seeds are very poisonous, so wash hands after handling

Problems: Occasional slug damage.

References: https://en.wikipedia.org/wiki/Veratrum

https://www.pacificbulbsociety.org/pbswiki/index.php/Veratrum

Text and images supplied by Anna Leggatt