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Search Results for ' Thuja'

PAL Questions: 6 - Garden Tools:

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Keywords: Pyracantha, Screens, Thuja, Hedges

PAL Question:

What shrubs or trees will grow quickly to provide a privacy screen above the 6 foot fence between me and my neighbor? My back yard is only about 20 feet from house to fence, and the first 10 feet is a concrete patio.

View Answer:

The classic fast-growing evergreens for hedges are Thuja 'Green Giant' or Leyland cypress (x Cupressocyparis leylandii), but they are a bit boring and because they grow so fast (1-3 ft/yr) it can be a big chore to keep them at a reasonable height. These trees do not stop at 8 feet, but could get to 30-50 feet.

Another fast evergreen is Pyracantha (Pyracantha crenatoserrata to ~8 feet). It is a shrub, but is easily trained/pruned to grow flat. In the past Forestfarm nursery in Oregon has sold both of these, as do most large nurseries. Be aware, however, that this shrub has fierce thorns!

Various types of bamboo could be an option for a fast screen, but plants may be expensive and running bamboo species MUST have a root barrier installed.

Season All Season
Date 2006-12-12
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Keywords: Thuja, Thuja plicata

PAL Question:

I have a golden cedar about 6 feet high. This winter many sparrows sat on the top portion while waiting their turn at the feeder. I don't know if they ate the leaves or if their little feet knocked them off, but many of the branches are stripped and brown. Will they come back? Should I cut them out and hope that new branches will fill in the spaces? It is approximately half of the front top of the tree. Or is it time to take it out? I would prefer not to, unless it can't be saved.

View Answer:

I am assuming that your golden cedar is a form of Thuja occidentalis or Thuja plicata. It is possible the sparrows caused the damage, but there could be other factors involved. It is difficult to tell without seeing the plant. Below are general comments on the liabilities of Thuja occidentalis as a landscape plant, previously available from the Ohio State University Extension website.

  • Winter evergreen foliage color is often an unattractive yellow-brown
  • very prone to bagworms and their feeding damage
  • very prone to branch separation under snow and ice loads
  • widens at its base with age, or separates into several leaning but divergent canopies with age (this applies to both upright and rounded cultivars)
  • does not recover from severe pruning (where the bare stems are exposed, although side branches may slowly envelope the dead stems)
  • interior foliage noticeably sheds in Autumn

The defoliation you describe might also be the work of bagworms. If the tips of the branches are dying back, that could be a result of winter injury, drought stress, or a fungal disease. Since I cannot diagnose the problem remotely, I think it would be best if you brought a sample of the affected plant to a Master Gardener Clinic. If you are in King County, this link to their website will lead you to the current clinic schedule.

Season All Season
Date 2007-04-26
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Keywords: Screens, Thuja, Juniperus, Viburnum, Hedges, Ceanothus

PAL Question:

I will be having a very overgrown, rarely pruned laurel removed from my back garden. It has been, if a monstrosity, an effective visual screen. The bare area that it leaves is appproximately 40' in length, is atop a rockery, approximately 3' high, and will look up into the neighbor's back hillside, while they peer down at us in dismay. Can you suggest one or several fast growing, shrubby plants or suitable trees that will act as an attractive visual screen? I do not want bamboo.

View Answer:

Here are a few ideas:

Morella californica

Thuja occidentalis 'Smaragd'

Osmanthus delavayi is also a good choice, but it doesn't get quite tall enough--my own hedge, which is pruned at least twice a year, is about 8 feet tall, so if I really let it go, maybe it would be 10-12 feet.

Juniperus scopulorum 'Wichita Blue'

Juniperus virginiana 'Manhattan Blue'

Viburnum tinus

Ceanothus would also be striking, with blue flowers, but you'd need to find the tallest possible species, and they tend to be short lived.

You could plant a mixed hedgerow, which would allow you to include some of the flowering plants you prefer. King Conservation District has more information on hedgerows.

Season All Season
Date 2007-09-13
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Keywords: Berberis, Trachelospermum, Euonymus, Taxus baccata, Screens, Thuja, Nandina domestica, Hydrangea, Ilex, Hedges, Clematis, Buxus, Bamboo

PAL Question:

Could you recommend some plants for a privacy screen that are also narrow? These would be planted in front of a fence in our backyard.

View Answer:

Here is some general information on plants for creating a screen.

Trees for Problem Landscape Sites -- Screening from Virginia Cooperative Extension

Good Hedges Make Good Neighbors from the United States National Arboretum

Bet on Hedges by local garden writer Valerie Easton.

Here is a list of narrow plants for a screen from local garden designer Chris Pfeiffer:

Fastigiate shrubs for naturally narrow hedges. Compiled by Chris Pfeiffer. 2005.

Zones 5-6:

American arborvitae ‘Rheingold’ (Thuja occidentalis ‘Rheingold’) 5’h x 3’w

Barberry ‘Helmond Pillar’ (Berberis thunbergii f. atropurpurea 'Helmond Pillar') 6’h x 2’w

Boxwood ‘Graham Blandy’ (Buxus sempervirens ‘Graham Blandy’) 8’h x 1-1/2’ w

English yew ‘Standishii’ (Taxus baccata ‘Standishii’) 4’h x 1-1/2’ w

Irish yew (Taxus baccata ‘Fastigiata’) 20’ h x 4’ w

Japanese holly Jersey pinnacle (Ilex crenata ‘Jersey Pinnacle’) 6’ h x 4’w

Japanese holly Mariesii (Ilex crenata ‘Mariesii) 3’ h x 1-1/2’ w

Zones 7-9, in addition to the above:

Dwarf yeddo rhaphiolepis (Rhaphiolepis umbellata Gulf GreenTM) 3-4’ h x 2’w

Heavenly bamboo ‘Gulf Stream’ (Nandina domestica ‘Gulf Stream’) 4’h x 2’w

Japanese euonymus ‘Green Spire’ (Euonymus japonicus ‘Green Spire’) 15’h x 6’w

You might also consider installing a trellis to increase the height of the fence, and then growing an evergreen vine such as Clematis armandii, evergreen hydrangea (Hydrangea seemanii), or star jasmine (Trachelospermum jasminoides).

This link is also helpful (scroll down to "Evergreen Vines" and look for appropriate height and light requirements).

You could grow bamboo, but I would recommend growing it in a container, or a series of containers, as you do not want the roots to spread. I have seen an effective bamboo screen between two houses growing in a long rectangular lined wooden trough (lined with bamboo barrier). Some species of bamboo are more tolerant of partial shade than others. Look for a clumping, rather than a running, bamboo (like Fargesia) to be on the safe side.

Growing Bamboo in Georgia

Running and Clumping Bamboos

Bamboos for hedges or tall privacy screens

Season All Season
Date 2008-01-03
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Keywords: Veronicastrum, Thalictrum, Actaea, Filipendula, Baptisia, Eupatorium, Berberis, Euonymus, Digitalis, Taxus baccata, Thuja, Verbascum, Helenium, Anemone, Ilex, Buxus

PAL Question:

I am redoing the narrow planting areas (2-3' wide) on either side of our 20' long entry. Garages from next door townhouses butt up against the outer edge on each side, causing morning sun and afternoon shade on one side, and vice versa on the other side. I have picked out some euphorbias, heucheras, and carexes which should do well. I'm wondering if I should have some taller, more dramatic plants to offset these and if you have any suggestions of ones which might work. Also, any bulb ideas would be appreciated.

View Answer:

Have you considered putting up trellises on one or both sides? Then you could grow vines which require little width, but still have the advantage of height. You could also grow taller plants (maybe some grasses like Miscanthus or even a well-restricted--using root barrier--Bamboo) in containers, and keep them shaped to suit the narrow space. Some shrubs and trees are naturally narrow or fastigiate in growth habit.

Here is a list of narrow plants compiled by local garden designer Chris Pfeiffer,c2005. Some will be too wide for your planting area, but you might want to research those that fit the site.

American arborvitae 'Rheingold' (Thuja occidentalis 'Rheingold') 5'h x 3' w

Barberry 'Helmond Pillar' (Berberis thunbergii f. atropurpurea 'Helmond Pillar') 6'h x 2'w

Boxwood 'Graham Blandy' (Buxus sempervirens 'Graham Blandy') 8'h x 1-1/2'w

English yew 'Standishii' (Taxus baccata 'Standishii') 4'h x 1-1/2'w

Irish yew (Taxus baccata 'Fastigiata') 20'h x 4'w

Japanese holly Jersey pinnacle (Ilex crenata 'Jersey Pinnacle') 6'h x 4'w

Japanese holly Mariesii (Ilex crenata 'Mariesii) 3'h x 1-1/2'w

Dwarf yeddo rhaphiolepis (Rhaphiolepis umbellata 'Gulf Green') 3-4'h x 2'w

Heavenly bamboo 'Gulf Stream' (Nandina domestica 'Gulf Stream') 4'h x 2'w

Japanese euonymus 'Green Spire' (Euonymus japonicus 'Green Spire') 15'h x 6'w

There are also a good number of tall perennials you might try, such as (for your afternoon sunny side) Helenium, Verbascum, Baptisia, Eupatorium, and bulbous plants like Allium and Eremurus, and for your shadier morning sun side, Macleaya, Digitalis, Filipendula ulmaria, Anemone hybrida, Actaea (formerly called Cimicifuga), Lilium martagon, Thalictrum, and Veronicastrum.

There are many excellent gardening books you could consult for ideas. Since you have a small, narrow space, I highly recommend local garden writer Marty Wingate's book, Big Ideas for Northwest Small Gardens (Sasquatch Books, 2003). You are welcome to visit the Miller Library, where you can do further research and also borrow books.

Season All Season
Date 2007-10-03
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Keywords: Thuja occidentalis, Plant longevity, Thuja

PAL Question:

What is the typical life of an arborvitae tree?

View Answer:

Arborvitae is the common name of Thuja, usually Thuja occidentalis. As with human beings, lifespan can only be an estimate, due to various circumstances which affect health and longevity. Urban growing conditions differ from those experienced by plants growing in the wild, for example. An article in The International Journal of Plant Sciences, Vol. 153, No. 1 (March 1992) by P. E. Kelly, et al. suggests that T. occidentalis growing on cliffs of the Niagara Escarpment in Ontario, Canada could be over 1,000 years old.

The record for this tree in the Urban Forest Ecosystems Institute database, SelecTree, indicates that its lifespan ranges from 40 to 150 years. Columnar arborvitae, Thuja occidentalis 'fastigiata,' is listed as having a lifespan of 50 to 150 years.

The Lady Bird Johnson Wildflower Center provides more information on Thuja occidentalis, too. Here is an excerpt:

"In a crowded environment, this tree is slender and not well-branched. In the open, it improves in form and density. The evergreen can be single- or multi-trunked and columnar or conical in shape. Eastern arborvitae can grow 40-60 ft. tall, but under cultivation will probably be no taller than 30 ft. Branches end in flat, spreading, horizontal sprays of fragrant, dark-green foliage which turns yellow-green or slight brown in winter. Resinous and aromatic evergreen tree with angled, buttressed, often branched trunk and a narrow, conical crown of short, spreading branches.

Probably the first North American tree introduced into Europe, it was discovered by French explorers and grown in Paris about 1536. The year before, tea prepared from the foliage and bark, now known to be high in vitamin C, saved the crew of Jacques Cartier from scurvy. It was named arborvitae , Latin for tree-of-life, in 1558. The trees grow slowly and reach an age of 400 years or more."

An article from the May 2002 issue of the Journal of Arboriculture lists Thuja occidentalis as a long-lived tree with a medium growth rate. They define "long" as over 200 years. However, most arborvitae one sees in urban landscapes would be unlikely to survive that long, due to many variables (poor planting methods, overcrowding, pollution, exposure to lawn chemicals, etc.).

Season All Season
Date 2008-05-07
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June 24 2013 12:55:25