Sunday, December 11, 2016

Evergreen Hedges - Tree Selection and Maintenance

     As Americans have rediscovered their back yards over the past several years and decided to spend more time in their current home because of the recent recession, more have decided to plant evergreen hedges.  The advantage of hedges are obvious - privacy, sound reduction from nearby streets and neighbors, habitat for wildlife, as a windbreak lowering heating costs in winter, and improvement in home value and curb appeal.  Unfortunately, we have seen a significant number of dead hedges over the past several years - mostly due to inappropriate trees for the area, inappropriately planted and insufficiently watered during the recent droughts.  We will attempt here to educate on the best types of evergreen tree for certain growing conditions, and how the Groasis Waterboxx might be useful in the planting of the hedge.  For the purposes of this post, we will only be discussing trees that grow at least to eye height (thereby blocking line of sight).

Arborvitae

      In the Great Lakes region where we are based, this is definitely the most popular hedge tree.  The Thuja occidentalis 'Emerald' variety seems to be the most commonly planted, but sometimes the faster growing if less picturesque Thuja standishii x plicata 'Green Giant' is used.  Both of these arborvitae (Latin for "tree of life") can be grown in zones 5-7, with the 'Emerald' variety hardy to zone 3 (see zones below).  
USDA Hardiness Zone Map - From Wikipedia
The 'Emerald' variety has a very nearly cylindrical appearance (with a slightly tapered spire), but tends to grow only about 12-18 inches per year, and reaches it maximum height of 20 feet slowly.  The 'Green Giant' variety can grow up to three feet a year under ideal conditions, and can potentially grow to 60 feet in height.  Both of the arborvitae are extremely sensitive to drought.  Over the last three summers, we have seen approximately 60% of established arborvitae die and 90% of newly planted arborvitae perish.  These trees, when bought potted from nurseries, almost always have a thick root ball when their base is removed from the pot.  Even when properly planted, these roots tend to stay near ground level, and will quickly dry out in periods of even partial drought.  One solution to deal with this is the rather arduous task of snaking a soaker hose throughout the trees every spring, and watering them thoroughly at least once weekly.  The soaker hose will need to be removed and stored before freezing in winter.  This can quickly become expensive, and tends to further cause roots to grow near the surface.  A (far cheaper) solution is to plant small bare root arborvitae (available from Arbor Day for as little as $2.49) using the Groasis Waterboxx.  The Waterboxx allows you to plant smaller, much cheaper (potted arborvitae sell for around $35 at big box home improvement stores due to the recent die off) arborvitae with properly formed roots.  The Waterboxx induces the roots of the tree to reach downward toward capillary water, not laterally (staying near the surface).  Because the Waterboxx contains a water reservoir and collects dew, you will not need to irrigate the trees after planting.  After approximately one year (depending on growth), the Waterboxx can be removed and reused.  You can calculate whether using a Waterboxx will save money during the first year using our calculator.  

Leyland Cypress

The Leyland Cypress (X Cupressocyparis leylandii) is also an excellent evergreen hedge tree, with the ability to grow much farther south than the arborvitae (up to zone 10).  The Leyland Cypress is also considerably more drought tolerant, as well as faster growing than the 'Emerald'  arborvitae.  The drawback to this tree is its mature size (up to 60 feet) and its susceptibility to infection.  As with the arborvitae, we recommend planting bare root Leyland Cypress using the Waterboxx, giving the tree an excellent foundation with deep roots.  The Waterboxx can be removed and used again to extend the hedge or to plant other trees.  
It is important to be a good (and thoughtful) neighbor when planting hedges, not planting tall plants that will block sun from reaching a neighbor's yard.  Also, each of the hedge trees discussed here can get certain diseases (arborvitae are susceptible to bagworms [Thyridopteryx ephemeraeformis] which appear to be pine cones at first sight) that will need to be dealt with immediately if spotted.  These diseases are more likely to take hold of unhealthy trees, another incentive to use the Waterboxx to properly establish the hedge at planting.

Be the first in your area to start growing plants with the Groasis Waterboxx. The Waterboxx can be purchased in the United States from Dew Harvest, with discount prices on orders of five or ten. We would love to hear your comments below - to leave one, please click on "Comments".