Amy Jo Detweiler
EM 9544 | Published March 2014, Reviewed 2025 | |

Selecting containers

Be sure your container has good drainage. Choose a container that is slightly larger than the total size of all the plants' rootballs combined, so they fit comfortably with a bit of extra space. Containers that have a lot of unfilled space retain too much water and encourage root rot.

Selecting soil

Always use an all-purpose potting soil that contains perlite or vermiculite, to allow for good drainage. Compost or bark provide organic matter that will hold moisture.

Selecting plants

Mix different plant shapes that include plants that are:

  • Spiky (usually in the center, often called Thrillers)
  • Mounding plants to fill in (fillers)
  • Trailing plants(spillers) that cascade over the sides.

Use a variety of leaf colors and textures.

Planting and care

Moisten potting soil before planting. To fill large containers more efficiently:

  • Place upside-down 1-gallon plastic pots at the bottom. This helps take up space and reduces the amount of soil needed.
  • Fill container with soil to within 1” of the lip of your container. This will allow you to create a water reservoir when watering.

After planting, water thoroughly. If you have a tray or saucer under your plant, be sure to empty it so the roots do not sit in excessive water.

For the rest of the season:

  • Water when the top 1-2” of soil is dry. Water thoroughly so that water comes out the bottom of your container to be sure you have saturated the soil.
  • Use a slow-release fertilizer or worm castings and apply several times throughout the season. You can also add these at the time of planting. To encourage lots of annual blooms, use a fertilizer high in phosphorous, such as 10-60-10.
  • Deadhead annuals throughout the season by removing spent blooms. This will keep them looking fresh.

Find more gardening tips in Gardening, Lawn, and Landscape.

Suggested annuals for container gardening

Thrillers

Usually buying just one or two per container.

  • Cordyline (cabbage palm)
  • Dracaena spikes
  • Purple fountain grass (Pennisetum)
  • Spider flower
  • Whirling butterflies (Gaura)

Fillers

Buy several in groups of three of each.

  • African daisy (Osteospermum)
  • Ageratum (Floss Flower)
  • Alyssum
  • Annual baby’s breath
  • Basil
  • Browallia
  • Cockscomb
  • Coleus
  • Cosmos
  • Dianthus
  • Dusty miller
  • Euphorbia Diamond Frost
  • Flowering tobacco
  • Geranium (zonal)
  • Impatiens
  • Lobelia, upright type
  • Marigold
  • Ornamental pepper
  • Pansy
  • Petunia
  • Plume Celosia
  • Pot Marigold
  • Salvia
  • Snapdragons
  • Verbena
  • Wax begonia
  • Zinnia

Spillers

Buy one or more.

  • Bacopa
  • Creeping zinnia
  • Licorice plant
  • Lobelia, cascading type
  • Million bells
  • Moss rose
  • Nasturtium
  • Spreading verbena
  • Swedish ivy
  • Sweet potato vine
  • Vinca vine
  • Wave petunia

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