Can anybody tell me what is the "fastest" of the Cedar-ish trees? We have unlimited ultimate height & breadth capacity. So far we have planted a couple of Sequoia Gigantica(?) and some Himilayan Birch and some maples. Soil here is heavy clay/loam varying to rocky in patches.
Rapid-growing hybrid Leyland cypress is popular, but rather scruffy. Under good conditions native Thuja plicata will also be fast-growing, as well as more handsome. Hedges of it are driven past on the freeway south of Vancouver. Hybrid with Asian species T. standisii, 'Green Giant' is on the market now, might be worth planting for novelty, although it probably serves primarily as a substitute for T. plicata in unsuitable climates elsewhere. Sierra redwood is Sequoiadendron giganteum. Coast redwood is also a fast-growing, monumental tree that will never blow over (unless badly rootbound).
I would suggest western red cedar (Thuja plicata ) and Lawson Cypress for fast growing evergreen conifers.
Since you're on Denman Island where water is scarce in summer, incense cedar (Calocedrus decurrens) would be a good choice. It's very drought tolerant and grows about 2' a year once established. It looks somewhat like a giant sequoia but forms a narrower column.
If Summer watering is limited that will propose to be a problem as any of the Conifers mentioned will have to be watered well for about the first 5 years until they adapt. I think specific cultivars of Coastal Redwood must be mentioned as your climate will be too cold for several forms that I know of. Soquel, Aptos Blue, Albo Spica (not to be confused with Adpressa or Albo Spicata) and Woodside would be your best bets but all but the first two will be iffy for you. They will require some serious babying from you. Aptos, Santa Cruz and Los Altos would have some definite problems with your coolness. If you want Coastal Redwoods stick with Soquel and Aptos Blue as they are the hardiest but growing them will not be a cakewalk for you and you will want to buy your trees in California and ship them in which can be an unpleasant matter to deal with. I would buy those Redwoods from a nursery near you that purchased their plants here rather than advise you to buy them from anywhere else. Planting Giant Sequoias on top of granite or a rocky underlying layer is a huge mistake. About a three foot deep hole in depth and also in width must be cleared of rocks before one can expect a 15 gallon sized tree to root in and establish itself well. Otherwise, it will do like many Coastal Redwoods do and that is just "sit there" for a long while and not grow in a cool climate. Site preparation incorporating in lots of humus is important for a Giant Sequoia and a Coastal Redwood anyway but in a cool climate it almost becomes essential. I like the Western Red Cedar, Incense Cedar and the Leylandii as well as Lawson Cypress recommendations but I just do not think of them as being fast growers in the Pacific Northwest. Here may be a different story but even then we do not get 2 feet of growth a year on established Incense Cedars unless we baby them. Just does not happen with any regularity grown in the wild or grown in less than ideal conditions. I am a little surprised that Deodar Cedar was not mentioned but perhaps Deodars do not do well for all of you but I could change that for you guys as there are some forms that are relatively fast growers, even in Oregon. Englemann Spruce can be a fast grower in the right locations but my first choice would be Douglas Fir. People just do not realize the growth potential of that tree especially with the improvement in certain selected seedlings. Plus, it keeps its shape when many of the false Cedars do not shape up well when they are young and forced to grow fast. It makes things difficult to want fast growth and have a "string bean" for a tree that looks ugly until it fills out years later. I'd rather have Conifers with moderate to fast growth and have some semblance of a shape. Eldarica Pines is another Conifer I would look as I've had good luck with it grown in a similar climate as you guys. That tree once it has been in the ground for 3-5 years can and does, for me, put on 2 plus feet of annual growth a year. Just some thoughts. Jim
Thanks for all the ideas Thanks to all for the ideas on shade trees. I'm interested in the Incense Cedar (I'll make pencils in my dotage) and surprised by the Doug Fir suggestion - several huge samples currently growing on the property will confirm that choice. Talk about "can't see the forest etc." Fortunately we have enough space to try all of them, and over time I'm sure we will. Other than shading the house, our current development project is a test patch of about a quarter acre of apple trees and grape vines which we hope to expand to several acres of each over the next few years. We hope to complete (the last 3000 feet) deer fencing this fall which should allow these plantings some chance of success. Water is not an issue for us as we have a reservoir of over 1M gallons with about 3000 gpd inflow even in the dry season.
Thuja Green Giants are an excellent choice for fast growing evergreens that provide shade. These guys can grow 3-5 feet a year and up to 60 feet tall and 20 feet wide! The Botany Store (www.botanystore.com) sell Thuja Green Giants online. They also sell Douglas Fir incase you want to go down that shady evergreen path!
Deodar is marginally the fastest-growing cedar, though Atlas Cedar and Lebanon Cedar are close behind.
The foliage appearance and aroma of 'Green Giant' is not as pleasant as that of the locally native arborvitae. It may not normally grow as fast, either.
