Dawn redwoods are hardy from zone 5 to zone 8. They will winter over well up here in Wisconsin (zone 4 and 5) with ample protection from the harsh wind.
Native to China and thought to be extinct for many years until a small grove was discovered in the 1930’s in the interior of China. Since the rediscovery they have been widely propagated throughout the world and are now are used as an outstanding landscape tree.
Dawn redwood is not very particular as to the soil they grow in but do prefer a well draining, acidic potting medium.
Do not over fertilize, as too large amounts of nutrients will cause long spindly shoots. Water as you would most of your bonsai but do not let stand in water.
Dawn redwood is pruned by pinching off the ends from the new shoots forcing them to branch out.
Small Dawn redwood made a very nice grove and a little larger (1″ to 2″ trunks) make a nice 3 tree grouping, and of course a large heavy trunk one will make a good formal upright, or one with shari up the front and some jins from the lower branches. They can also be trained into a flat top like the old bald cypress that grow in the swamps of the deep south.
“Bonsai Bob” Eskeitz