Container Gardening in a Nutshell
by Diane Linsley and Andrea Steen
Whether your garden is large or small, you
can enjoy growing plants in pots. Potted
plants make nice focal points in the garden.
They also bring the garden right up to the
front door, making the entrance to your
home more inviting.
Container Gardening Basics
1. Group plants according to their needs
for water, fertilizer and sunlight.
2. Start with good-size transplants.
Containers draw attention to themselves,
so they need to look nice right away. Seed-grown plants should be started indoors 4-8 weeks early.
3. Make sure the container has good drainage, unless you are doing a bog garden in a pot.
4. Use quality potting soil. Some potting mixes include slow-release fertilizer and wetting agents or polymers. If your mix doesn’t include these, you can add them in small amounts. Plan on fertilizing once a week with a balanced fertilizer (preferably organic), even if the potting mix includes fertilizer. Unlike plants in the garden that can spread out their roots in search of nutrients, potted plants must be fed regularly.
5. Mulch with cocoa shells or buckwheat hulls for an attractive finish that helps retain moisture.
6. Water at least once a day.
7. Keep the plants deadheaded and pruned to look their best. In a container, there’s nowhere for scruffy plants to hide. If a plant isn’t working, replace it with something else. Although dwarf annuals are usually preferred, taller varieties may be used if they are pinched back before bloom to keep them compact. An example of this is cosmos, which comes in various heights.
Choosing Plants
Sun or Shade: There are plenty of plants for full sun to part shade, but fewer choices for full shade. Recommended full-shade plants include begonia, browallia, caladium, coleus, ferns, fuschia, impatiens, hosta, ivy and lamium. See the following article for Shade-Tolerant Flowers.
Color Schemes: Color combinations are a matter of personal taste. But in general, bright and bold colors are preferred because they stand out. Pastels can work if the container is to be viewed up close, like next to the front door.
Proportion: The size of the plants, including their flowers and leaves, should be balanced with the container. Many popular annuals come in dwarf forms that are suitable for containers. In Contain Yourself, Kerstin P. Ouellet says, “As a rule of thumb you should aim for the plant portion to be at least twice as big as the visible part of the container.” But don't overplant because crowded plants will be prone to diseases and pests. Remember that plants grow!
Plant Habit: A variety of plants with different habits makes a potted garden more interesting. Kerstin P. Ouellet recommends combining upright, mounding and trailing plants. In hanging baskets, the upright element can be replaced with another trailer or climber.
Here is Andrea Steen’s 3-component recipe for a container garden. It works especially well for hanging baskets, as you can see in the picture at the top of this article.
2. Add a trailing filler like alyssum, bacopa, bidens, brachycome, helichrysum, lobelia, nolana, sanvitalia or verbena.
convolvulus. The vine can be trained up the chains of the hanging basket. In non-hanging pots, the vine is trained on a small trellis or an interesting tree branch for a sculptural touch. Push the branch into the soil, and anchor it with rocks to keep it stable.
4. Optional: Add a foliage plant like coleus or sweet potato vine.
Texture: Containers aren’t just for flowering plants. Beautiful potted gardens can be created by juxtaposing foliage plants with different leaf shapes and textures. Consider leaves that can be described by the following adjectives: wide, narrow, coarse, fine, shiny, fuzzy, heart-shaped or ferny. Use different shades of “green” to increase the visual delight. How about chartreuse, blue-green, silver-gray, bronze or variegated?
Ornamental grasses are becoming very popular for container gardens. Grasses add the dimension of motion. Stipa tenuissima is a favorite because it sways gracefully in the slightest breeze. Grasses and other foliage plants are especially nice when combined with flowers. In Gardening in Containers, Gary Keim says, “More than anything else, foliage gives body to container groupings. It provides the backbone and adds color to reinforce the floral display.”
Simplicity: Don’t try to do too many different things in one container, or it will end up looking messy. Most containers look best with 3-5 different plants. For large containers, rather than adding more different plants, try using larger groups of the same plants. If you’re longing for extra color, make one of the plants a mix. For example, instead of using a single-colored cosmos, try Cosmos ‘Dwarf Sensation’. Other popular mixes include Nasturtium ‘Jewel Mix', Snapdragon 'Magic Carpet' and Zinnia ‘Thumbellina Mix’.
Containers with a Purpose
With so many ideas to choose from, where do you start? It might help to identify a theme or purpose for your container garden. Here are some ideas.
Fragrant Garden: It’s always nice to have fragrant flowers in window boxes or containers on the patio where you’ll be sure to enjoy them. Try sweet peas, stocks or alyssum. Don’t forget plants with fragrant leaves that you can rub as you walk past like lavender, Agastache cana or curry plant (Helichrysum italicum).
Rock Garden in a Pot: I enjoy making my own cement planters for small, drought-tolerant perennials like cactus, sedum, and hens & chicks. There are hundreds of possible rock garden plants. Some can even be grown from seed. Here are some ideas: Rock Garden Perennials.
Container gardening can quickly become addictive. Once you master the basics, you may find yourself staging whole groups of container gardens....
Recommended Books
The Ultimate Container Gardener by Stephanie Donaldson
Contain Yourself by Kerstin P. Ouellet
Gardening in Containers (Fine Gardening Design Guides)
