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Sunday - April 14, 2013

From: Niles, MI
Region: Midwest
Topic: Invasive Plants, Non-Natives, Privacy Screening, Shrubs
Title: Covering dead arborvitae with non-native ivy from Niles MI
Answered by: Barbara Medford

QUESTION:

I have a severely thinning arborvitae hedge. It is probably too shady, but I want the privacy. I'm thinking of planting something like ivy to fill the gaps. I know it will probably kill the hedge, but in my weird mind, I see a hedge of ivy on the bones of the arborvitae. Will it work?

ANSWER:

We are curious about why your arborvitae is declining, whether it is getting too much/not enough water, sunshine, etc. Until you know what your situation is there, we would not suggest you plant anything else.

There is a plant native to North America, which is all we will recommend, as well as to Michigan - Thuja occidentalis (Arborvitae). There is also a Thuja called Thuji orientalis or Platycadus orientalis that is native to Korea, Manchuria and Northern China. Nurseries sometimes use a familiar plant name without specifying what the plant actually is. A plant out of its native range is much more likely to experience damage from the wrong soils, insects, diseases, etc. than those native to the area.

We're not crazy about the idea of a dead shrub being used as a framework for anything, but especially not English Ivy. Here is an article about Hedera helix (English Ivy) that we hope will help to convince you not to plant it, because once you plant it, you HAVE it and it won't go away. Regardless of its name, it is native to most of Europe and western Asia and most invasive.

So, let's take a whole new look at a way to obtain privacy. First off, we're not satisfied with the word "hedge." That always brings to mind something squared-off and boxy looking, and somewhat unnatural. How about calling it a "linear grove"? (We just made that up.) We have in mind several shrubs we can recommend for your purposes, but they are not all going to grow uniformly, especially when they transition from sun to shade. You'd probably be happier leaving them casual and mostly untrimmed, because if they manage to get up to 15' tall, it's going to be a challenge to prune them back and keep them out of power lines. Also, you can mix your choices according to the amount of sun or shade each area receives and each plant requires.

Go out and survey the area for sunlight. We consider "sun" to be 6 hours or more of sun a day, "part shade" 2 to 6 hours of sun and "shade" 2 hours or less of sun.

We will go to our Recommended Species page, click on Michigan on the map and find a list of 156 plants recommended for your state. Using the right-hand sidebar on that page, we will sort on "shrub" for Habit and 6-12 ft. for size range. You can repeat the search with "tree" for Habit and different size ranges, and also the Light Requirements you have discovered for the area. This is just an example to show you how to use the database. If you rethink your requirements for total screening, you will see that a mixed planting between your property and the one next to it will distract the eye and differentiate the two areas. All are native to the area of Berrien and Cass Counties so they will be adapted to your weather conditions. Follow each plant link to our webpage on that plant to discover its growing conditons, water and sun needs, soil preferences, etc.

Cephalanthus occidentalis (Common buttonbush)

Corylus americana (American hazelnut)

Cornus sericea (Redosier dogwood)

Physocarpus opulifolius (Atlantic ninebark)

Rhus glabra (Smooth sumac)

Spiraea alba (White meadowsweet)

 

From the Image Gallery


Arborvitae
Thuja occidentalis

Common buttonbush
Cephalanthus occidentalis

American hazelnut
Corylus americana

Red osier dogwood
Cornus sericea

Atlantic ninebark
Physocarpus opulifolius

Smooth sumac
Rhus glabra

White meadowsweet
Spiraea alba

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