The Garden Guy: Reasons to Choose Your Next Plant

botanicgardens.uw.edu

Earlier this month, the Garden Guy stopped by a number of garden centers to see what was still available in this year of live goods shortages. Whether I was at Fred Meyer, Home Depot or Swanson's, my conversations with other gardeners usually included the topics of this summer’s unusual heat waves and the (re)evaluations of lagging plants in the landscape. 

It concerned me that many people were looking for a quick ‘little something’ to fill the hole left by the perennial or shrub that had succumbed to the weather. It concerned me that immediate gratification usually took the place of considered research when would-be gardeners were in the process of choosing their next plant. 

I referred to the ‘class’ I informally ran through multiple times that weekend as ‘Reasons to Choose a Plant for the Garden’ and, who knows, it might just turn into one of the actual lectures I present around King County.

Heat - earthobservatory.nasa.gov

Given the heat-related gardening issues I heard from others, plant hardiness and climate change should be among a gardener’s initial concerns. Greater Seattle is usually considered to be a USDA Zone 8 region. 

However, we do occasionally have a worse-than-usual winter; so, consider purchasing plants that are good down to Zone 7 or 6. On the other end of the scale, plant hardiness to Zone 9 or 10 is also a good thing as our summer become hotter. Theses hardiness zones are usually listed with the plant. 

A related issue is drought-tolerance. Once the plant is established (think three years after transplanting), can it survive with a minimum of water? If these pieces of information are not included with the plants you have your eye on, do a bit of immediate smartphone research on the internet before making the purchase.

Research the full size of a plant

If you are spending $50 for a shrub OR $250 on a tree, doesn’t it make sense to spend five minutes checking the climate tolerances and growing conditions for a potential new addition to your landscape? 

You might want to consider planting a rockrose (Cistus) rather than a rhododendron.

Speaking of rhodies, how many times have you noticed shrubs crowding out their neighbors or a full-size tree growing way too close to the house? 

These issues can be alleviated by researching the mature size of a plant. Remember that plant tags usually provide you with the plant size after ten years of growth. But, plants, like people continue to grow after that point in time, just a bit slower. 

 House and Tree #1 - bas eco.net

I have rhododendrons in my back yard which reached the stated 6’ x 6’ size after ten years as was noted on the plant tag. But, fifteen years beyond that, they reached 10’ x 10’ and 12’ x 15’, respectively. 

Luckily, they were provided with enough room when I initially planted them (and, yes, after I moved a few other shrubs to different spots in the yard.)

This plant size information is particularly important with trees. 

Mature trees are not easy to relocate, are costly to have removed and even more costly if they damage a building foundation or roof. 

House and Tree #2 - aaatree.net

Remember that the cute, little five-gallon twig you want to purchase may really need to be installed fifteen to twenty feet away from the side of your home.

Also, with trees, there are a few other factors to consider. 

Evergreen trees, be they needle or broadleaf, create a continued presence in the landscape and they are great for continual screening and shading. 

They do, however, grow at a slower rate than their deciduous counterparts. 

Between evergreen and deciduous candidates, I will almost always vote for the leaf-dropping specimen. 

Yes, deciduous trees may be messier than evergreens, but they make-up for that failing with quicker growth, flowers, colorful leaves and interesting, sometimes colorful, bark in winter.

Cercidiphyllum japonicum
/Katsura Tree

Beyond the aesthetics of deciduous trees, I enjoy the practical aspect of their ability to lessen my utilities bills. 

When planted on the south or west sides of a home, deciduous tree reduce the amount of summer sunshine reaching and overheating the building, thus holding down air conditioning costs. 

Conversely, with the arrival of winter and the loss of leaves on branches, sunlight more readily reaches the walls of a home which help warms the building and reduces heating costs. 

In addition, after leaf-fall, new vistas in your neighborhood are opened for changing visual interest.

Finally, let’s consider ‘the WOW Factor,’ AKA, color spots in the landscape. 

Color is one of the great benefits of perennials, shrubs and trees in the home landscape. And, do think beyond the usual ephemeral spring and summer flowers. 

More permanent color can be had and enjoyed through the use of leaves, bark and berries.

 Cornus alba 'Elegantissima' leaf - OSU

With some plants, home owners can experience three and four seasons of different WOW reasons. 

In the effort of full transparency, I must admit that evergreens can come in a variety of green, yellow and blue shades that will provide more interest to your yards. 

Flowers can add colors from white, to red, to blue, and just about everything in between. 

For the rest of the year, think about the advantages of adding red or yellow stems, variegated bark and/or colorful berries along with the usual autumnal leaf colors.

 

Cornus alba ‘Elegantissima’/
Variegated Redtwig Dogwood

Thinking in longer terms than what you see in the garden center now will add to your long-term enjoyment of the little piece of heaven you call home.

If you need other reasons to choose a new plant, let me know and I’ll decide if another article on the topic is needed.

The Garden Guy

Contributing gardening columnist, Bruce Bennett, has been a WSU Master Gardener, landscape designer and lecturer for more than twenty years. He is the managing partner of a Seattle-area garden design firm and is an instructor with WSU Extension’s College of Agriculture, Human and Natural Resources. Contact Bruce with your plant problems, gardening questions and article suggestions at gardenguy4u@gmail.com