How to Combine Plants
Tuesday, August 14, 2012 at 5:01AM A recent commenter asked if I would focus on some plant combinations. It is a huge topic, and whole books have been written on the subject. I will mention a few basics to remember, and the rest is as flexible as the gardener's imagination.
First, plant companions that are similarly hardy and have the same light, water, and soil requirements. You can break this rule by planting some things in pots, in which you can alter the hardiness, soil, and water requirements. I have a few tropicals in pots that will come inside for the winter, and I have a couple of potted plants whose soil requirements could not be met in my native soil.
Second, plant in layers. Nature does this, with a canopy of taller trees, an understory of smaller trees and shrubs, then a layer of plants close to the ground. If you plant everything of the same height, the garden will lack dimension, even if the plants are all beautiful. 
Above shows a section of the front garden. The different layers with varying textures, shades and forms provide interest, though only crepe myrtles are blooming. The tree in the center is my beloved 'marriage tree', a Japanese maple. Peacock Orchid foliage below it creates a vertical element. Other plants include azaleas, weigela, yaupon hollies, and forsythia.
Tall pine and oak trees form the canopy over much of the woodland garden. The photo above shows a section of the middle and ground layers. Japanese maple 'Waterfall' arches over spreading yew and frames a bench in the background. On the other side of the moss path is the ground cover Vinca major under some large trees. This is a woodland ground cover and should never be allowed into a flower bed.
Above is another good understory shrub for the woodland garden, Viburnum dentatum, shown blooming in a springtime photo. I love the hosta 'Elegans' which grows beneath it. Cool blue green is a color that is repeated throughout the woodland garden.
Third, repetition will unify the garden and relate plants to one another. There are several ways to do this:
1. Repetition of the same plant in different areas of the garden will create a flow that pulls the garden together. It is good to have groups of the same plant, unless there is a specimen plant that you wish stand alone.
Dwarf Yaupon hollies, shown in the foreground and also seen across the lawn, are low maintenance native shrubs that grow naturally in a rounded form. I use them throughout my gardens to create structure and provide a sense of unity.
2. Repetition of color. I like to combine plants where the primary color of one is repeated to a smaller degree in another:
Plectranthus and Stromanthe tricolor are beautiful together, though neither are hardy in my area. The stromanthe is in a pot, and I will bring it inside to protect it from winter frost.
While foliage always stars in my garden, I do have some flowers! Below are some color combinations I enjoy. Clockwise from above left: In the front planter are dusty miller, a salmon colored petunia that echoes the color of nearby stonework, and purple blooming heliotrope; In the wildflower garden, orange cosmos reflects airy golden solidago, while garlic chives bloom in between; The colors of a Japanese maple are found in an iris; A bright orange zinnia in a hanging pot repeats the colors of a Tropicanna canna lilly in the background.
Another way to unify with color is to combine plants of the same color, using various shades, shapes, and textures.
Shades of blue repeat in this vignette by the parking court. Blue salvia and silvery artemesia 'Powis Castle' combine well with the little blue cypress growing in a steely blue planter.
'Waterfall' Japanese maple grows in front of Juniper 'Saybrook Gold', which covers part of a bank in the woodland garden.
Even an all green area can be beautiful:
Different shades, as well as different forms and texture, provide interest.
3. Repetition of form:
This is not in my garden! I took this photo at Biltmore Estate in North Carolina. I love how the weeping form of the Blue Atlas Cedar is echoed by the smaller shrub and in the curve of the path. Even a large tree branch above has a similar arch. Notice also that the bench reflects the color of the cedar.
Above is another view with the 'Waterfall' Japanese maple: I love how the colors of cream, gold and green combine here, as well as how the vertical reach of the heuchera flowers is reflected in the background by liriope and iris foliage.
Finally, introduce an unusual element for a delightful surprise. Who would expect a tropical red banana plant amidst roses, rosemary, and lacy spirea?
I don't think it is out of place, and I love that red banana plant. Remember to plant what makes you smile, and your garden ultimately will reflect your heart and soul. Happy gardening!
By the way, you may be interested in a book, Fine Foliage, which is coming out soon. Written by two professional garden designers, fellow blogger Karen Chapman and Christina Salwitz, it describes foliage combinations and why they work.
Reader Comments (20)
Absolutely beautiful examples of form, repetition, color variation and use of foliage. It all just looks so inviting that you don't even think about the design and the careful combinations that went into these layers of the garden. It just works! But you explain why --- very instructive.
Your garden is a fine example of really good plant and planting combinations Debs! :)
Thank you for a wonderful post! I learned a lot - I usually just plant what I like, and I end up with a big jumble! Also, I have purchased stromanth for several years now - it's one of my favorite plants, but I didn't know what it was or how to look it up. (I buy them from a tropical seller who shows up in the spring, and he never knew the name of it.) Your gardens are gorgeous - I especially love the woodland gardens!
Wonderful post Deb, showing wonderful contrast of texture, shape and colour and that's just the foliage! It all adds up to a garden that is calm, peaceful and just invites exploration.
Deb, It is always a treat to visit you. Your photography is dreamy and gorgeous . . . capturing the magic in your garden. Wonderful post! Thank you for your kind words. ;>) I hope you are enjoying the summer . . . that it is not too hot or dry. Carol
Perfectly described Deb, your woodland looks so natural but nature is rarely so well designed. I love it. Christina
Nice ideas and illustrative images, Deb. You're a fine design tutor. All best.
Great post Deb and as you know a subject I am passionate about! Learning how to put plants together is key to good design and you explain it so well.
Thanks so much for mentioning my new book Fine Foliage too. If your readers enjoyed this post as much as I did they will find this book helpful, inspirational and total eye candy!
This is a great post! Such a clear exposition of basic principles, with wonderful photos to illustrate. This one got tagged and saved for future reference.
You laid out the tips very well, organized and concise. So many need the advice is such a manner, making design understandable and easy to execute when you hear and see the ways to do it . Your use of foliage is done to perfection.
Thank you so much for the mention of our new book "Fine Foliage" in this most lovely post. Clearly, it's a topic near and dear to our hearts. You did a beautiful job with it!
Gratefully,
Christina Salwitz
Your foliage is always so impressive. I am more heavy on the flowers but working on native foliage plants more...we shall see. Great ideas for companion planting and a few I will be trying to do better with
I always pick up a good hint or two when I read your posts....thanks.
Going back to look my garden with new eyes.
Jen @ Muddy Boot Dreams
I've probably said this before: Wow, your garden is like a woodland paradise! I'm still learning many of the tips that you're sharing. It took forever for me to grasp the concept of layering.
Hi Deb
Excellent points and photos to illustrate plant combinations! I loved the blue hosta with the Viburnum dentatum. You've shown how to combine plants using colour, form and texture. This is great for all gardeners from beginners right up to experienced ones. It's always fun to learn something new.
Love the little blue planter with the dog. Beautiful photos and garden.
Very good guidance. I would only add to plant everything in large groupings to make a statement.
Great post. Some great tips and advice here.
I love your shots of the front garden and your 'Waterfall' maple!!
Beautiful !!! Great pictures, love the hostas and Deodar cedar trees, you have a magnificient garden.
I planted two Deodar Cedar trees last year that I got a good deal on at our local nursery. They are fast growing, they have put on nearly 12 inches this year. We just moved into our new home last year so everything in our yard is very young. check out my Deodar;;
Deodar Cedar