Screens and Windbreaks

Screens and Windbreaks

 Where a windbreak is desired or a year ‘round screen, large evergreens such as pine and spruce should be planted.  Consider using conifers (cone bearing trees or needle evergreens) on the perimeter of the property to block undesirable views or winds.  Generally such a screen planting would be used to shelter and warm the house by blocking the cold winter winds.  You might also want to hide a bad view with a dense evergreen tree while leaving desirable views open.   

This is a topic near and dear to my heart.  I grew up in an urban “subdivision” with neighbors just 20’ away from our patio.  I always thought about how the quality of life in this situation could be so much better with some privacy screening.  Good fences make good neighbors!   Just one or two, or better yet, three evergreen trees strategically planted can make a huge difference in the enjoyment of your back yard.  I’ve seen hot tubs placed on a patio with no fence or screening of any kind and wide open to the view of 8 or 10 neighboring houses.  That just doesn’t make sense.  In fact, what I’m about to tell you regarding screen and windbreak plantings is really just good common sense.

For example, as always, keep it natural.  Don’t plant the trees in straight rows.  This will just set you up for disappointment when one tree dies or grows more slowly than the others.  Trees aren’t bricks.  They are individuals.  Regardless how badly we want them to all grow identically, they will be slightly different.  You should spend time placing marking flags in the area to represent the trees.  You might start by standing on your patio or at your kitchen window and place flags to hide the bad views.  Look at your flags from all directions to see that it looks pleasant and natural.  Be sure you are covering the bad views.  Check that no 3 trees are in a straight row.  Large pines and spruce should be planted about 15’ apart for best coverage when they mature.

Newly planted windbreak

There are a couple of exceptions to the “don’t plant trees in a straight line” rule.  It’s a different circumstance when space is limited such as along a fence in a narrow yard or when lining a driveway.  In this case a straight row might make sense.  Just be aware that your trees should be planted at least 12-15 feet from the property line to avoid crowding.  Branches growing across your neighbor’s property line belong to your neighbor and might get pruned off.   When planting along a driveway, you need to allow plenty of room for the trees to grow and not crowd the driveway.  Little spruce trees planted 5 feet from the driveway will someday have to be taken down or pruned up to allow passage down the drive.  I’d suggest at least 20’ of space between the edge of the driveway and the trunk of any tree.  Shade trees might even be given more room.  Low branched shade trees like willows and pin oak should never be used to line a driveway.  This is a prime example of what I’m talking about when I say you could be planting a “liability”.  Another problem with planting evergreens along a driveway is trapping snow.  A line of evergreens will work just like a snow fence.  This is good if they are planted 150’ from the driveway keeping the snow drift away.  But if your “snow fence” is close to the driveway, that’s where the snow will be also.

Regarding plant selection, it’s a good idea to mix several species to guard against attack by potential insect or disease problems.  Pest problems on plants are usually the result of a specific insect or disease attacking a specific type of tree.  By mixing various species of pine, spruce, fir etc., you will reduce the likelihood of an epidemic destroying your group planting.  If you are trying to cover a large area, you might even mix in some deciduous trees or shrubs to further enhance your barrier planting.  Shrubs planted on the inside of a screen of evergreens will help with the density in summer as well as adding flower color against the dark green background.

You might also consider mixing the sizes of the trees you are planting.  Think about it.  This would enhance the natural appearance of your planting, while averaging out the cost of the entire project.  One rule of thumb when planting trees is that it takes about 1 year per inch trunk diameter for a newly planted tree to become established and resume growth.  In other words, the larger the tree that’s being transplanted, the longer it will take for it to recover from the “transplant shock”, get its roots established and start to grow again.  In fact it’s common that a smaller tree will often start to grow sooner and eventually catch up with and pass a larger transplanted tree.  This doesn’t mean that seedlings will surpass a larger transplanted tree.  But a 3’ tree might catch up to a 6’ tree planted at the same time after a few years.  It takes about 5 years for a small seedling to grow into a bushy little 3’ tree.  Of course with small seedlings planted out in a large lawn many other problems are possible such as weed competition, lawn mower pruning and rabbit or rodent damage.

Avoid planting evergreens in low spots!  This is generally true of all plants when planting in heavy clay soil.  Clay soil is “tight” and poorly drained with little air space.  Roots require aeration.  When planted in low areas most plants will be stunted at best but will often suffer and eventually die.  Of course there are exceptions.  Plants that would normally grow in low swampy areas or stream courses, like willows or bald cypress, will do well in wet spots.  If done properly, this could be a storm water retention area or “rain garden” and result in a nice feature in your garden.  However pines and spruce in screens will require good drainage.  One or two feet of mounding is helpful if the area is flat.  If your screen planting goes through a low spot you’ll notice the trees in that area will not do well.