A Fervor for Clivias

May, 2021

In late spring, as daylight in the Pacific Northwest stretches to 15 hours and beyond, blossoms burgeon in all parts of the ever-brightening garden. At present my gaze is held in thrall to three clumps of Clivia miniata ‘Flame’ I’ve been growing just outside my front door for more than a quarter century. This year a quintet of fiery orange inflorescences, each boasting 12 to 20 trumpet-shaped blossoms, illuminate the shady north entrance to the house.

As clivias are native to forested coastal regions of South Africa, they happily adorn gardens galore in California, Australia and other Mediterranean climate zones. In fact, they are so easy and dependable that they verge on being clichés in mass public plantings from Seville to Sydney. However, in most temperate but frost-prone areas, including our own, these bold, perennial, evergreen amaryllis relatives are usually grown as reliable, elegant, and long-lived houseplants. Yet as my 25 years of experience attest, if proper procedures are observed, one can successfully grow clivias outdoors year-round in the PNW. The two essentials to their survival here are shade and shelter. Let’s consider each element.

In Sonnet 18 Shakespeare wrote, “Rough winds do shake the darling buds of May,” but a clivia couldn’t care less about gusty breezes —its mortal enemy is direct sunlight, which scorches and disfigures the lustrous, deep green foliage. As the Bard noted a bit later, “Sometime too hot the eye of heaven shines.” Clivias have it made in the shade; they even thrive in near total darkness for weeks at a time, as we’ll see below. That said, a bit of tangential sunlight early or late in the day won’t hurt, and even produces spectacular backlighting.

Clivias need shelter from winter wetness and from freezes. This may seem like an unavoidable double whammy in our neck of the woods, but here’s what I do: 1) Take advantage of the wide eaves of my midcentury modern house to provide both shade and protection from winter rain. My largest and oldest clumps grow in a 20-inch wide, 8-foot long bed squeezed between brick wall and sidewalk directly under the eaves. 2) Swaddle the plants in several layers of burlap bags or old blankets in case of a deep freeze or heavy snowfall. Clivias tolerate a few degrees of frost if provided overhead shelter. If the forecast is for 28 degrees or colder, out comes the stack of burlap from the garage. I’ve left my clivias covered for up to three weeks at a time during lingering outbursts of Arctic air.

If the structure of your home doesn’t provide an exterior covered shelter, try planting under a broad evergreen. I’ve plopped down a couple dozen seedlings near the base of a huge, limbed-up Rhododendron ponticum, a deodar cedar, and a western red cedar. Some specimens planted beneath the cedars not only have thrived, but also bloom each year. If you forget to cover, or if the freeze is worse than predicted, all or a part of the clivia may shrivel up or turn to mush, although it will usually resprout in late spring or early summer.

Other important cultural tips: Clivias need at least two months of cool autumn evenings to set buds properly in late winter. I grow some cultivars in pots that live outside in summer shade and are only brought back inside in late November. Remember that clivias need to be dry in winter. Stop watering them —whether in the ground or in containers— in October and don’t resume until the flower stalk emerges and buds are about to open. For house-grown plants this usually happens from late January to March. My outdoor, in-ground plants produce slow-growing bud stalks in January that don’t fully open until late April or early May. If you’re lucky you’ll get a second bloom in late summer or early autumn.

It’s gratifying and remarkably easy to grow clivias from seed. You may need to hand pollinate your housebound bloomers, but if you do so you’ll be rewarded with cherry-size fruits that take about 10 months to mature. You’ll know they’re ready to harvest when they turn red, as in the photos. Each fruit contains two to four large seeds (about the size of a small macadamia nut). Although they germinate quickly on a bed of damp sand or between moist paper towels, it takes four to five years until they reach blooming size.

Next session —the last before we pause for summer— we’ll explore how to nurture waist-high Aeonium cultivars.

Horticulturally yours,

Daniel