Gardening Essentials: Thrillers Fillers and Spillers
Create Gorgeous Containers for Your Deck This Season
“I must have flowers, always and always.” — Claude Monet
I embrace that sentiment, and come spring I must have flowers always and everywhere, especially on my deck. Growing flowers in containers is my solution, and the more varied the containers themselves are, the better. Thriller. Filler. Spiller. Let these three words guide you when choosing plants for your containers. As a rule of thumb, a 12-inch diameter pot needs one “thriller,” two “fillers” and three “spillers.” A thriller is the focal point of your design. Usually it is a tall, structural plant with colorful foliage or a striking form that provides an anchor for the other plants. The thriller is usually the first thing I choose for the container.
For years, dracaena spikes were the most commonly used thriller. An annual plant in our zone, it has long, narrow swordlike leaves. Small ornamental grasses, cordyline (another spiky annual with wider leaves), or any upright growing annual such as the coleus in the photo to the left, can be used as thrillers.Fillers, you may have guessed, refer to the plants that add mass to your container. Usually a mounding-type plant, they are planted around the thriller. Supertunias, verbena, calibrachoa, begonias, dusty miller, angelonia and smaller coleus are just a few good fillers.
Spillers, by now you must suspect, are plants that spill over and soften the edges of your container. Good spillers, when planted at the edge, include sweet potato vine, licorice plant, bacopa, vinca vine, lamiums and also Supertunias, verbena and calibrachoa.
Over the years, I’ve learned to see potential containers in many objects other than standard flowerpots. For instance, the container in the first and largest photo didn’t come from a garden center; it was purchased in the kitchen section of a discount store.
To make sure it would hold soil, I lined the container with burlap. Burlap can be cut and folded easily to fit any container, but it works especially well with those that are oddly shaped. The secret to making burlap easy to work with is to soak it first in water. Then be generous with it. I usually use at least a double layer in all my wire/mesh containers. Allow for a generous portion around the edge so it can be folded back into the container and covered neatly with dirt.
When filling your containers, use a quality potting mix, not soil you dig out of your yard. There is no need to put new potting soil in a container each year. I have used the same soil in a container for many years. With smaller containers, I might remove much of the soil, break up any clumps, and perhaps add a bit of fresh soil before putting it back.
All plants grown in containers need good drainage. With larger containers, make sure there are several drainage holes.
A really large container does not have to be completely filled with soil. Years ago I put rocks in the bottom of large containers, but they can make the container too heavy to move. Broken pieces of plastic foam, empty plastic soda bottles, or anything else lightweight that occupies space can be placed in the bottom one-third to one-half of a 2- to 3-foot-deep container. If using pieces of plastic foam, it’s a good idea to place them in net bags, like the kind onions are sold in, before putting them into the container. This makes it easier to remove them from the soil.
The downside of container planting is that these plants are dependent on you to receive adequate water and fertilizer. Mixing a slow-release fertilizer, available at any garden center, into the soil before planting will supply much of the nutrition the plants need.
Depending on the weather and the size of the container, some may need to be watered as often as twice a day during a sunny, hot, dry spell. If the soil dries out completely, it will shrink from the sides and become difficult to rehydrate, making it hard for water to reach the plants’ roots. This problem can be fixed sometimes by placing a dried out container into a larger one filled with water for a couple of hours.
One final note: Don’t be afraid to prune the plants in your container during the summer. If a plant looks too long and leggy, cut it back. It will reward you with healthier, bushier growth.
Then, sit back and enjoy your flowers, always and everywhere.