Trillium erectum is a perennial herbaceous plant that grows to about 40 cm (16 in) in height with a spread of 30 cm (12 in). It can tolerate extreme cold in winter, surviving temperatures down to −35 °C (−31 °F). Like all trilliums, its parts are in groups of three, with a 3-petalled flower above a whorl of pointed triple leaves.
Once established in the garden, trillium wildflowers require little maintenance or care. As long as they have been planted in a suitable location, you need only keep the soil evenly moist, but not soggy. They may also require water in dry weather.
Fertilizer is not necessary as long as they have plenty of organic material or compost mixed into the soil. You can, however, renew this each year if desired.
Red Trillium. This plant grows to about 40 cm (16 in) in height with a spread of 30 cm (12 in), and can tolerate extreme cold in winter, surviving temperatures down to −35 °C.
Although young, tender trillium leaves are nontoxic, North Carolina State University Extension reports that trillium roots and berries are mildly toxic, causing symptoms that are unpleasant but not severe or long lasting.
