Korean Maple

Today's Question
"I live in zone 5B (Kingston Ontario) .. I am very interested in a 'Korean Maple' tree aka 'Acer pseudosieboldianum' .. have you any experience with this tree and if so could you tell me what you think of it?"

Acer pseudosieboldianum, commonly referred to as Korean maple or purplebloom maple (the bloom and seed colour). It is listed as being USDA Zone 4 hardy, the species has been grown successfully in Bismark, ND (USDA Zone 3), suffering no damage at temperatures to -43º F (with a heavy snow cover).

For your interest, the 'pseudo' in pseudosieboldianum means 'a false or not' in reference to a Japanese maple.

While the species tolerates full sun and wind, it really is much happier with protection from a heavy afternoon sun/wind combination. Korean Maples will grow in shade, but show the best fall color in sunny locations. The Korean maple is sold as  single stemmed grafted tree, or as a multi stemmed large shrub. In it's native home, it grows as a large shrub.

Like any garden plant, the species is not problem-free. Although individual trees are reported to be winter hardy in Zones 3 and 4, some seed lots have been found to be considerably less winter hardy. Similarly, while the species has been reported to have vivid fall colors, the literature contains reports of the species displaying muddy greenish-brown fall colors. Like many maples, Korean maple is thin barked, rendering it susceptible to mechanical damage and winter sunscald damage, the latter most often occurring at the site of mechanical damage. Mechanical damage to the trunk and stems can also provide sites for disease infections. Currently, the main liability of the species appears to be it's susceptibility to a canker disease (Nectria, Eutypella, Valsa and/or Cryptosporiopsis) which enters the tree at wound sites, causing dieback of the infected branches or stem. Fungicides can be used in conjunction with pruning or at wound sites to protect against infections, although there are no fungicides labeled for such use. The principle management strategies include maintaining plant vigor with adequate water and fertilization and the removal and destruction of infected twigs and limbs to prevent the spread of additional inoculum.

I would add, "Watch for aphids, as they do tend to like this small tree."

Several Garden Centres have attempted to market Korean Maples in the Canadian Prairies, they have had little success. Our occasional -40°C early winter days without a snow cover,
   --- usually sends them to tree heaven rather quickly!