When is herb gardening like painting? When it’s in the hands of someone who combines an artistic eye with sound knowledge of the plants’ requirements. Approached artfully, herb gardening in containers can go way beyond the usual strawberry pot with a different species planted in each pocket. Combination containers can bring herbs together in a way that highlights each herb’s color, texture, flower, and growth habit. They’re a perfect way to experiment with the elements of garden design on a small scale and for a relatively small investment.
They’re also one of the hottest-selling items for spring and summer at Rabbit Shadow Farms, a greenhouse in Loveland, Colorado. Well-known for years for its topiaries, Rabbit Shadow began selling containers with herb combinations four years ago, and over the last two years has seen an increased interest in them. Head gardener Kristie Janes designs the containers to delight the eye first, though many of them are also planted around various themes–herbs for Italian cooking, for example, or herbs that flower in white and yellow.
At the entrance to the garden center’s greenhouse, container herbs and topiaries cluster around a pond, fountain, and wrought-iron garden bench, inviting visitors to sit and admire them. Bright pansies peek from pots of dark green curly parsley; the tiny, pale blue blooms of rosemary draw the eye into a backdrop of basil and oregano.
Rabbit Shadow co-owner Jeff Sorenson has seen interest in container gardening steadily increase. At the Denver Botanic Gardens’ spring sale this March, orders for Rabbit Shadow’s combined containers quintupled. The majority of people who come to the sale are knowledgeable gardeners, he says. They use the containers and plant arrangements that they buy as patterns for others they plant themselves.
Popularity aside, Janes says she finds the containers so much fun to design that they’re addictive. “They are an artistic release, and I am not really artistic,” she says.
Inspiration in a pot
Which comes first, the pot or the plants? Great containers often announce themselves to the eye at a flea market or garage sale, or call to you from the corner of a friend’s planting shed. It’s the imperfections that inspire, Sorenson says. Old toolboxes, pails, cans–anything that is recyclable that you can add drainage holes to and fits the style of your overall garden will do. Janes likes to add trellises to pots for climbing herbs such as nasturtiums.
Just keep in mind an allowance for some growth; once you have your plants chosen, add up the diameters of their root balls. Your container’s diameter should be about 2 inches larger than the total. If it isn’t, subtract a plant or two–then you’ll have an excuse to do another container plant combination.
Both Sorenson and Janes recommend clay pots for breathability. Clay promotes healthy root systems by releasing soluble salts; it also helps water drain evenly. If you choose plastic pots, be sure not to water too frequently; keeping the soil supersaturated will retard the growth of the plant. Much of your watering routine, however, will depend on your local climate and the location of the pot. The only sure generalization is that a new container will need frequent checking–as often as twice per day in dry, hot areas–to make sure that plantings aren’t over- or underwatered. Once you know how quickly a planting drains and how rapidly it tends to dry out, you can set a watering routine that will keep it happy–but you’ll still have to adjust that routine as the seasons change.
Soil for combination container plantings is critical. A trustworthy planting mix keeps herbs healthy and allows for good drainage. Janes likes to use a pre-mixed blend of peat, vermiculite, and perlite. Both Sorenson and Janes recommend Premier Pro Mix, which has a neutral pH. For really large containers, they may add wood chips to the bottom of the pot to facilitate drainage without adding weight. (Be sure such chips are from wood that hasn’t been chemically treated, however; don’t use chips from plywood or pressed wood products.)
Choosing herbs
Among hundreds of species and cultivars, narrowing them down to just a few can be difficult. Both Janes and herb container guru Rob Proctor, co-author of Herbs in Pots (Interweave Press, 1999) recommends starting with a theme, be it color, culinary use, fragrance, or a completely whimsical conceit. In Proctor’s Denver garden, for example, are old teapots planted with Roman chamomile, various mints, and scented pelargoniums–all useful in tea, hot or iced. Proctor also suggests grouping herbs for an ethnic cuisine in a single 18- to 20-inch pot.
In Janes’ creations, you can also see this concept at play. An Italian culinary pot features basil, parsley, and several oreganos. A French container supplies French thyme, chervil, rosemary, and lavender. Basil, cilantro, chives, and parsley fill a Southwestern pot; choose Thai basil and add tiny Thai peppers to keep the kitchen supplied with Asian herbs. Throw in a pepper or tomato plant for color, and you’ve got a pot that can be raided to make a homemade salsa or sauce.
Janes is particularly fond of pots themed around fragrance, so she loves working with lavenders. To her, a French gray lavender (Lavandula dentata var. candicans) gives off the most powerful fragrance, with the species L. dentata coming in second. Two other lavenders, ‘Hidcote’ and ‘Munstead’ (both L. angustifolia), are hardy and drought-tolerant, making them good container candidates, she says.
She also chooses color as a frequent theme. One eye-popping trellis pot she created focuses on herbs and plants that bloom in whites and yellows. Golden feverfew, nasturtiums, chamomile, and a variegated jasmine provide lots of variety in foliage shape and color, so the pot is attractive even when the herbs are not in bloom. She suggests mixing a medley of gold-toned plants–golden lemon thyme or ‘Doone Valley’ thyme, variegated lemon balm, and ‘Norton’s Gold’ oregano. Sometimes she mixes contrasting colors. For purple and silver, try planting ‘African Blue’ basil with silver thyme–then throw in a splash of color with ‘Goodwin Creek’ lavender and purple violas or pansies.
Proctor focuses on the shape, color, and texture of foliage and the growth habit of the plants, rather than ephemeral blooms. “Flowers come and go,” he writes, “but leaves provide constant interest throughout the season.” Janes’ containers illustrate his point; she often works with variegated or dwarf versions of thyme, oregano, and marjoram, and sometimes includes a small herb topiary. Some of Rabbit Shadow’s most interesting containers are “fairy gardens”–pots that incorporate miniature furniture, trellises, or fences made of twigs. Janes sometimes strews pebbles across them in miniature paths or includes a tiny chair with its legs planted deep in the soil.
“I like to use a lot of different textures, which makes the fairy gardens interesting,” she says. “I like to add silver plants. I use different flower combinations, but mostly texture and color are what I play with. And I like to have something upright or trailing that will climb up a trellis or fence.” Climbers mean that a container garden’s shape and balance will change as it grows, continuing to provide visual interest.
What goes where?
You’ve got your theme. Now you need to choose herbs with similar growth habits; you don’t want to mix sun-lovers and shade-lovers, nor those that love moisture with those that don’t. (For growing habit suggestions for particular cultivars, see “Less Space? More Herbs!” April/May 2001). Many herbs like a light potting mix with light fertilizer, plenty of sun, moderate pruning, and occasional watering, but find out the requirements of each plant you choose.
Kristy Sorenson, Jeff’s sister and the co-owner of Rabbit Shadow, suggests arranging the plants by thinking in terms of a visual field. Begin with your tallest herb at the center; place others around it in decreasing order of height at full growth. At the edges or the perimeter, place creeping or trailing plants. Another way to conceptualize arrangement is as a pyramid form: uprights in the back, trailing specimens in front, spreading types in the middle. While the herbs are still in their original pots (or just after transplants have been dug), set them together in a rough approximation of your arrangement. If you don’t like what you see, rearrange. Pay attention to the overall balance of the composition, but mainly let your taste guide you. Once you’re happy, plant them.