07 March 2013

Cold Hardy Camellias


Camellias have historically been a warm-climate flowering shrub.  However, many new varieties are cold-hardy to USDA zone 7 and a few are cold-hardy to zone 6.

Camellias are in the Tea (Theaceae) plant family. Camellia sinesis leaves and buds are used to make the green and black teas we drink. Linnaeus named Camellias after a Jesuit missionary, George Kamel. Tea camellias are native to Southeast Asia where they have grown for centuries.

U.S. gardeners began making improvements on the Camellia japonicas in the 1700s and by 1960 cold-hardy camellias became available. Two American breeders, Dr. William Ackerman and Dr. Clifford Parks developed the best hybrids.
Camellia kanjaro - Greenleaf Nursery
Fall-blooming Ackerman hybrids succeed in our region and include: Winter Star, Winter Rose, Winter Snow, Winter Interlude, Pink Icicle, Snow Man, winter’s Charm, Snow Flurry, Ashton’s Snow, etc.  (See http://alturl.com/2x9dn for an Ackerman article on growing camellias in cold climates.)

Inexpensive camellia plants can be purchased but it is best to select fall-blooming hybrids that will survive heat, humidity, cold, drought and downpours. Cold-hardy camellias to look for are hybrids of japonica, oleifera Plain Jane, oleifera Lu Shan Snow, saluenesis and especially sasanqua.

Barry Fugatt, the horticulture director of the Tulsa Garden Center and the Linnaeus Teaching Garden said, “The spring blooming camellias are vulnerable to late frost and bud burn that can ruin their flowers.”


 fall blooming Camellia sasanqua Han Jiman
photo courtesy of Greenleaf Nursery
With regular, deep watering, Camellia sasanqua varieties can take our summer drought and still bloom in the fall. Fall-blooming Yae Arare has pink edged single flowers and Showa No Sakae has rose-like pink flowers. 

Fugatt said that the camellias he has at home are not on a watering system. Instead he gives them a deep soak once a week.

Placement for camellias is the same as we think of for azaleas according to Fugatt:  Acidic soil, dappled sun, afternoon shade and consistent moisture.

“I am impressed with the performance of cold hardy camellias,” Fugatt said. “After the first 2 or 3 years, they grow into your soil and prove to be durable.”

The other growing advice Fugatt provided is to minimize fertilizer.

“Too much tender spring growth is hard on the plants and looks unattractive,” Fugatt said. “Use either a manure product or Osmocote slow-release fertilizer in the fall instead of spring.”

There are exceptions but most camellias grow very slowly, maturing at 4 to 9 feet tall and wide. A Camellia sasanqua might grow to only 3-feet tall over a period of 5-years.

Greenleaf Nursery (www.greenleafnursery.com) is the grower of Espalier Winter’s Snowman Camellia. It is ideal for a tight space since it grows up to 12-feet tall and stays skinny at only 5-feet wide at maturity.  It is cold hardy to zone 6 which is 0 to -10 F. The flowers are large, white, anemone-form. Espalier Autumn Pink Icicle, has soft pink flowers and is cold hardy to zone 7.

Greenleaf also grows October Magic Snow camellia which has frilled, magenta-edged, double white flowers. Their camellia Hana Jiman has pink-edged semi-double white flowers. Hana Jiman is a southern heritage plant that grows 10 feet tall and 5 to 12 feet wide.

Unlike azaleas, camellias grow a tap root, helping them withstand dry spells and cold winters. Like azaleas, they prefer 5.5 to 6.5 soil pH, shelter from wind and a location at the northeast side of a heated building that leaks warmth all winter.

Plant camellias high with the trunk base above the soil line. Protect them in summer with thick mulch and in winter surround the roots with paving stones that will hold warmth.  Clean up leaves as they drop to prevent disease.

Gardeners who lost azaleas during the past two years might want to replace them with camellias in April.

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