Color Theory and Foliage

  • Difficulty Rating: Beginner
Variegated cannas, dwarf variegated agaves, sedums and grasses are as beautiful as flowers on a hot summer day

Green may calm our senses, but let’s add a little caliente to our borders this year. Treat yourself with a rainbow from soft blue or silver, to dark purple, chartreuse, yellow and even orange.

Consider Tropicanna® cannas as your guide to this spicy mix. The original orange and pink leaf dances to a Latin beat, but now there are black and gold introductions to tempt you too.

Setcreasea pallida 'Purple Heart' and pentas are proven performers in summer gardens.

Next to cannas, place Solenostemon scutellarioides (syn. Plectranthus for some types), coleus. Coleus are grown as annuals throughout most of the U.S. because they originally hail from Africa, southeast Asia, India and Australia. Square stems tell you they are part of the mint family, and as diverse and spicy as Indian curry. In the beginning, coleus were only grown in the shade. Now, sun coleus are part of every greenhouse arsenal. Some like Big Red Judy® grow to enormous heights while others are quite small.

Sun coleus ‘Finger Paint is a lively mix of red, orange, yellow and green.

Another group of tropical foliage plants back in vogue is the genus Alternanthera, Joseph’s coat. Only a few years ago, you rarely saw them, but different selections are now for sale everywhere. Some alternantheras have delicate structure while others are big and bold. While most are grown from cuttings, ‘Purple Knight’ grows true from seed. Alternantheras can be planted in a sunny border, but you will likely see some leaf burn in a sizzling summer.

Black and chartreuse sweet potato vines mix with coleus in these window boxes.

Acalypha, copperleaf plant, is another diverse genus. Even though it isn’t as common as coleus, it is grown as a shrub in Florida and further south. Where copperleaf is a tender tropical, it still makes a bold statement in the summer border, or as the centerpiece in a container. A. wilkesiana ‘Kona Gold’ is shown below.

Acalypha wilkesiana 'Kona Gold' copperleaf plant is a bright addition to a sunny border.

Don’t neglect old standards like Strobilanthes dyerianus, Persian shield, Iresine herbstii, chicken gizzard plant, and Setcreasea pallida, purple heart, all which grow better and better the hotter summer gets. Purple heart also has a variegated form with hot pink stripes, a twist on an old favorite.

Cordylines were once considered only houseplants north of Florida. Now, however, they adorn containers and borders throughout the South. Rhoeo spathacea, oyster plant, is another great tropical foliage plant for the front of the border.

Persicaria microcephala ‘Red Dragon’ is very easy to grow.

Persicaria microcephala 'Red Dragon,’ above, is an easy plant with beautiful variegated foliage. This cultivar is considered sterile and does not spread by stoloniferous roots like others in its genus.

Fantastic foliage isn’t limited to tropical plants. Japanese maples and perennials can be combined like this red selection and the variegated wand flower below.

Japanese maple and variegated wand flower make a great pair.

As for shrubs, there are so many diverse ones on the market now. Variegated Abelia x grandiflora ‘Kaleidoscope’ mixes beautifully with solid green plants. For dark beauties, try Black Lace® Sambucus nigra ‘Eva’ (elderberry), or purple Cotinus (smokebush). Smokebush can be grow as a small tree or medium shrub.

Foliage can take your garden from a dull and difficult summer to one that shimmies with the heat. Try something different this year, and you too will become a foliage fan. Believe me . . . once you stroll over to the spicy side, you’ll never go back.