Creating a container garden

Posted by tonka_admin on Apr 19th 2014

Not every garden needs to be planted in the ground. Tonkadale Greenhouse specializes in creating container gardens, large and small, for indoor or outdoor enjoyment. The first step is to select the appropriate container for your garden. Choose the right size for the space you want to fill, and make sure it's not too heavy to move it if you need to do so. The material of the container also can make a difference in the success of your garden. Here are some of the advantages and disadvantages of some common materials.

Cast iron

Advantages: Durable, elegant, classic designs, neutral colors. Can tolerate winter conditions. Disadvantages: Heavy. Rust can damage surfaces. Cast iron will heat up in the sun.

Glazed pottery

Advantages: Many shapes and sizes. Bright and bold colors. Statement pieces. Good value. Disadvantages: Not always tolerant of freezing and thawing. Heavy to move.


Advantages: Lightweight. Easy to move. Grays and neutral colors. Durable. Disadvantages: Can be an expensive option. Fading, chipping and material breakdown can be a problem.


Advantages: Elegant designs in many classic styles. Good water retention. Stands up against the elements. Disadvantages: Heavy. Weathers with time.


Advantages: Lightweight. Inexpensive. Good water retention. The “look for less.” Disadvantages: May not be as durable. Fading can be a problem. Temporary.


Advantages: Bright colors. Antique looks available. Good water retention. Disadvantages: Heats up in the sun. Can rust or dent. Weathers with time.

Terra cotta

Advantages: Classic planter styles. Good for smaller plantings. Disadvantages: Not durable in winter conditions. Dries out quickly through evaporation.

Iron stone

Advantages: Weather resistant. Stands up to freezing and thawing. Natural and earthy colors. Disadvantages: Heavy to move.


Advantages: Lightweight. Less expensive option. Disadvantages: Can break with impact. May not stand up to the elements.


Advantages: Natural product. Easy for do-it-yourself projects - choose your color or stain. Disadvantages: Weathers with time. Rooting may be a problem. [rev_slider containerblog2014] [gap height="30"]

Setting up your container

Choose a potting soil with good drainage, water retention and organic matter. Tonkadale recommends our special Tonka Terra mix. We want you to be successful with your containers. Tonkadale recommends that you use fresh potting soil each growing season. Over time, important soil properties for proper plant health deteriorate. Nutrition, porosity, water retention and drainage all decrease with time and use. Tonkadale recommends that annual plants be given 12 to 18 inches of fresh soil for any container garden. The bottom of the container can be filled with a filler of your choice:
  • Pop cans.
  • Old plastic grower pots.
  • Milk jugs.
  • Gravel (if weight is needed).
  • Packing peanuts.
  • Old plastic pots.
  • Ups-a-Daisy Planter Inserts.
Remember, if your container is top-heavy, add weight to the bottom of the container for ballast.


Drainage is a must for all container gardens. If your container doesn’t have a hole, you can drill one, poke one or cut a hole into the bottom of the container. Another option is to use a drop-in or liner. This is simply a plastic pot (or a pot made of another inexpensive material) that fits the depth and diameter of your container. The benefits of using a drop-in are many:
  • They provide drainage if your decorative pot does not have proper drainage.
  • They reduce the risk of damage to your pots due to freezing and thawing temperatures in the winter.
  • They make it easer to change your containers from season to season. All you need to do is simply lift the drop-in out of your pot and dump its contents, plants and all, and you are ready to start again for the next season.
We do not recommend using a layer of gravel at the bottom of your container to provide adequate drainage. Gravel should be used only to provide ballast and weight if your container is lightweight or top-heavy.

Exposure and light requirements

Know your site. Pick the right plants for your light exposure.
  • Full sun — 6 or more hours of full sun
  • Part sun — Less than 6 hours of full sun, morning sun
  • Shade — Dappled light, filtered light, indirect light, less than 4 hours of sunlight
There are many gradations when it comes to light requirements. The intensity of the sun can increase with reflection, wind and temperature. Ask us and we can help you choose the right plant for your pots.

Picking your plants

At Tonkadale, we always say “foliage first.” Use foliage as the architecture of your container. If the flowers weren’t there, would your container still look good? There are many tropical and exotic foliage plants that work great in containers. House plants and perennials can be used, too. Another rule of thumb: “Big and chunky, fun and funky.” Choose a few key elements to highlight in your containers. This creates more impact and drama Tonkadale relies on a few quintessential recipes for sun and shade For shade: Fern, begonia, ivy. There is a lot of diversity in these elements. You can switch out one element for another with similar height, such as ferns; blooming power,  such as the begonia; and trailing characteristics, like the ivy. For sun: A spike, cordyline or grass, geraniums, coleus, petunia, potato vine. Within these different plant varieties, there is great diversity.  No two people will end up with the same container if you use this recipe. When all else fails, start at the coleus table. The experts here always know to lead you in the right direction.  And of course, Tonkadale always has a plethora of sun and shade containers all planted up and ready to go!  That’s a great place to draw inspiration or just grab and go.  We won’t tell your neighbors that you didn’t plant it.

Fertilizing and watering containers

Watering requirements will vary based on:
  • Sun exposure.
  • Material of the container.
  • Temperature.
  • Wind.
  • Rain.
The easiest way to tell if your container needs water is to stick your pointer finger into the soil up to your second knuckle. If the soil feels moist, there's no need to water.  If the soil feels dry, get out the hose or watering can. Annuals are hungry plants. It is best to fertilize on a regular basis during the growing season. Tonkadale carries many traditional and organic fertilizer options in both liquid and slow-release formulations. We can help you choose the best fertilizer for your needs.

Need help?

Containers are what we do best at Tonkadale. We are happy to help you plan a container for every season. Visit Tonkadale for seasonal inspiration and ideas. We have many talented designers on staff to create your containers for you.