Lawn and Garden

Container Gardening

John W. Jett
WVU Extension Service
Extension Specialist – Horticulture

Introduction

If you don’t have space for a vegetable garden or if your outdoor space doesn’t provide the necessary elements to produce the flower garden you’ve always wanted, consider the possibility of “container gardening.” A patio, deck, balcony, or doorstep can provide enough space for a productive, attractive display.

If you live in an apartment with limited outdoor space, you might consider doing a little indoor gardening. By using sunny window sills, you can grow a number of herbs.

Benefits

Many individuals find container gardening to be advantageous. Each person is unique and has his or her own particular circumstances. They may be:

  • disabled with a need for easy accessibility
  • gardeners with problem soil
  • homeowners with little or no land
  • elderly with limited mobility
  • apartment/condominium dwellers
  • cooks—gourmet and otherwise
  • plant lovers who just can’t get enough of nature

Convenience

While space (or lack of it) is an obvious reason to try container gardening, that is not the only reason people choose this method. Often, convenience plays a big part, especially for vegetables and herbs. Having these essentially at your fingertips is a tremendous advantage. The mobility of container gardening makes it easy to rearrange and resculpture your garden and to add new elements of interest and beauty.

For busy two-worker families who don’t have time to produce a large garden, a number of well-placed pots on the deck often can do the trick. For the elderly who can’t garden anymore, sometimes a simple tomato plant conveniently located by the back door may be enough to satisfy the craving for fresh vegetables and to recall memories of days past.

Economy

Smaller spaces result in smaller costs. Initial set-up costs may be a little more, but once the appropriate containers and materials are purchased, costs are minimal. You will be buying fewer plants, less media, and less fertilizer than for traditional gardening.

Time

Families today are busier than ever and gardening is time consuming. Container gardening reduces the amount of time you spend tending plants. Whether you plant ornamentals or edibles, care is minimal. Time-release fertilizer and automatic watering systems can reduce that time even more.

Display

Just as a garden can be a work of art, a well-planned container garden can be attractive as well as useful. Carefully selecting plants will result in a beautiful, yet functional display.

What you’ll need:

Appropriate Containers

Containers are available in many sizes, shapes, and materials. All containers, whether clay, wood, plastic, or ceramic, should have an adequate number of holes in the bottom for proper drainage. Additional holes should be drilled or punched in containers that do not drain quickly after each watering. Setting the container on a solid surface, such as a cement or patio floor, reduces drainage. Raising the container one or two inches off the floor by setting it on blocks of wood will solve this problem.

The container’s size will be determined by the plant selected. Generally, most plants grown in the soil can be grown in containers as long as ample space is provided for them to develop roots. Shallow-rooted crops like lettuce, peppers, radishes, herbs and most annuals need a container at least 6 inches in diameter with an 8-inch soil depth. Bushel baskets, half barrels, wooden tubs, or large pressed paper containers are ideal for growing tomatoes, squash, pole beans, cucumbers, and deep-rooted perennials.

Media

A fairly lightweight mix is needed for container gardening. Soil straight from the garden usually cannot be used in a container because it is too heavy, unless your garden has sandy loam or sandy soil. Clay soil consists of extremely small (microscopic) particles. In a container, the bad qualities of clay are exaggerated. It holds too much moisture when wet, resulting in too little air for the roots. Also, it pulls away from the sides of the pot when dry.

Container medium must be porous in order to support plants, because roots require both air and water. Packaged potting soil available at local garden centers is relatively lightweight and may make a good container medium.

For a large container garden, the expense of prepackaged or soil- less mixes may be quite high. Try mixing your own with one part peat moss, one part garden loam, and one part vermiculite or perlite, and a slow-release fertilizer (14-14-14) added according to container size. Lime may also be needed to bring the pH to around 6.5. In any case, a soil test is helpful in determining nutrient and pH needs, just as in a large garden.

Fertilizer

Fertilize plants with the recommended rate of a water-soluble fertilizer every two to three weeks. An occasional application of fish emulsion or compost will add trace elements to the soil. Do not add more than the recommended rate of any fertilizer. Doing so may cause fertilizer burn and kill your plants. Unlike garden plants, container plants do not have the buffer of large volumes of soil and humus to protect them from over-fertilizing or over-liming.

Water Requirements

Pay particular attention to watering container plants. Because the volume of soil is relatively small, containers can dry out very quickly, especially if they are on a concrete patio in full sunlight. Daily or twice-daily watering may be necessary. Apply water until it runs out the drainage holes.

Water clay pots and other porous containers more frequently, as they allow additional evaporation for the sides of the pots. Small pots also tend to dry out more quickly than larger ones. If the soil appears to be getting excessively dry (plants wilting every day is one sign), group the containers together so that the foliage creates a canopy to help shade the soil and keep it cool.

Check containers at least once a day and twice on hot, dry, or windy days. Feel the soil to determine whether it is damp. Mulching and windbreaks can help reduce water requirements for containers. Consider installing an automatic trickle irrigation system if you plan to be away for extended periods.

Light Requirements

The amount of sunlight your container garden spot receives may determine which crops can be grown. Check light requirements for specific plants. Available light can be increased somewhat by providing reflective materials, such as aluminum foil, white-painted surfaces, and marble chips, around plants.

Plant Material

Plant breeders have helped to make container gardening more practical by breeding plants having compact growth habits. Almost any vegetable and annual and perennial flower can be adapted to container culture. The possibilities are endless.

You may want to use the following plant categories that can be used when creating your container garden.

Edibles

  • Vegetables
  • Herbs
  • Fruits

Ornamentals

  • Annual flowers
  • Perennial flowers
  • Exotic foliage
  • Bulbs

Plants suited for container culture 1

Vegetables Beans, Bush Eggplant Peppers, Bell
  Beets Kale Squash, Summer
  Carrots Lettuce, Leaf Tomatoes
  Cabbage Mustard Greens Tomatoes, Cherry
  Chard, Swiss Onions, Green Turnips
  Cucumbers
     
Annual Herbs Anise Basil
  Chervil Coriander
  Dill Summer Savory
     
Biennial Herbs Caraway Parsley
     
Perennial Herbs Chives Fennel
  Lovage Marjoram
  Mint Tarragon
  Thyme Winter Savory
     
Fruits Apples (dwarf spur-type)
  Blackberries Blueberries
  Raspberries Strawberries
     
Annual Flowers Ageratum Dusty Miller Pansy
  Alyssum Geranium Petunia
  Begonia Impatiens Salvia
  Celosia Lobelia Snapdragon
  Coleus Marigold Verbena
  Dianthus Nasturtium Zinnia
     
Perennial Flowers Achillea (Yarrow) Lupine
  Aquilegia (Columbine) Rudbeckia
  Candytuft Sedum
  Chrysanthemum Shasta Daisy
  Gaillardia Veronica
  Gypsophila  
     
Exotic Foliage Alocasia Lantana
  Banana Palm
  Caladium Phygelius
  Cannas (variegated and
red-leafed varieties)
Pygmy Date Palm
  Coconut Schefflera
  Dracaena Variegated Ficus
  Elephant Ears White Bird of Paradise
  Hibiscus  
     
Bulbs, Fall-planted Crocus Scilla
  Daffodil Tulip
  Iris  
     
Bulbs, Spring-planted Begonia Gladiolus
  Dahlia Oriental and Asiatic Lily


1 Consult catalogs for cultural requirements and varieties adapted to container culture.

Planting

Plant container specimens at the same time you would plant them in a regular garden or flower bed. Fill a clean container to within 2 inch of the top with a slightly damp soil mixture. Peat moss in the mix will absorb water and blend much more readily if soaked with warm water before the mix is put into the container. Sow the seed or set transplants according to instructions on the seed package or plant tag. Put a label with the name, variety, and planting date in each container.

After planting, gently soak the soil with water, being careful not to wash out or displace seeds. Thin out seedlings to obtain proper spacing when the plants have two or three leaves. If cages, stakes, or other supports are needed, provide them when the plants are very small to avoid later root damage.

Activities

Let’s make a mixed container of annuals.

  • Use several varieties of flowers and foliages in pleasing combinations of color and texture.
  • Design the container plantings for shade or sun, combining only those flowers that have similar cultural requirements. Semperflorens bronze-leaved begonia or any of the green-leaved begonias, impatiens, Pretty-In-Red salvia, and coleus work well in containers in shady areas. For sunny locations, the choice is almost unlimited.
  • Include plants for height (e.g., Shasta daisies or geraniums), plants for spread (e.g., petunias,) and plants to grow down over the edges of the containers. Trailing foliage plants are useful here, as well as those that flower, such as hanging fuchsias and verbena.
  • Plant too much rather than too little. Err on the side of extra plants for a lush, full effect. But to compensate for extra plants, fertilize and water properly. Apply a slow-release fertilizer for summer-long feeding. Water abundantly throughout the summer.

Here are a couple of ideas for container planting combinations that work well.

  • Pink and white full-sun container: pink begonia, white nicotiana, rose-pink geranium, white petunias, white snapdragon, pink vinca.
  • Blue and pink shade container: pink impatiens, pink begonia, violet impatiens, dusty miller, and alyssum.

References

Bartholomew, Mel, Square Foot Gardening, St. Martins Press, 175 Fifth Ave, Room 1715, New York City, NY 10010, 1981

Berry, Susan and Bradley, Steve, Contained Gardens, Ballentine Fawcett, Division of Random House, 201 E 50th Street, New York City, NY 10022, 1995

Holmes, Roger, Taylors Guide to Container Gardening, Houghton Mifflin, 222 Berkley Street, Boston, MA 02116, 1995

Yang, Linda, The City Gardeners Handbook, Random House 201 East 50th Street, 22 Floor, New York City, NY 10022, 1990