Planting your best

Container Garden

Gardening season has finally arrived and it ’s time to freshen up those outdoor containers with gorgeous annual color. But how many plants do you actually need? It’s easy to seek instant gratification and overfill containers from the start—but when it comes to container gardening, patience pays off.

Finding the right balance between containers looking full at the beginning of the season and giving them space to grow and fill out can be tricky, but knowing how many plants you should use in a container makes all the difference.

thriller • spiller • filler

where to start

So, how many plants should you use in your container? A good rule of thumb for container gardening is to start with one thriller, at least one spiller, and then use fillers to complete the rest of the design. Starting with a standard 12-inch container, for example, we recommend using 3-4 quart-sized plants:

1 Thriller | Plant that grows upright, serving as the tall focal point of the container
1 Spiller | Plant that spills over the edge of the pot and grows downward
1-2 Fillers | Plants with shorter, bushy to spreading habits that fill the spaces between thrillers & spillers

container design

20" ceramic planter

Growing in a larger container, like the one pictured, allows for more flexibility with plant sizes and selection. Instead of filling this 20-inch pot with 8-10 quart-sized plants, we used 6 quarts and one 8-inch centerpiece (about the size of two quarts) to create a more robust feel from the start without compromising space for the plants to grow and fill out.

1 Thriller | 8-inch Canna Cannova® Golden Flame
3 Spillers | Quart Sweet Potato Vine ‘Bright Ideas Rusty Red’, white Dipladenia & Superbells® Yellow
3 Fillers | Quart Coleus ColorBlaze® El Brighto, 2 Quart SunPatiens® Compact Electric Orange

container design

16" ceramic planter

Growing in a standard 16-inch pot, like the one pictured, typically starts with 5-6 quarts. For this example we used:

1 Thriller | Quart Angelonia Angelface® Blue
2 Spillers | Quart Supertunia® Saffron Finch™ & Quart Superbells® Over Easy™
2 Fillers | Quart Alternanthera Plum Dandy™ & Quart Nemesia Aromance® Mulberry™

by the numbers

knowing how many plants to install in one pot

Not sure where to start when it comes to building your own container? Here’s a quick guide to know just how many plants you should start with each season.

6″ Container | 1 Quart
8″ Container | 1-2 Quarts
10″ Container | 2-3 Quarts
12″ Container | 3-4 Quarts
14″ Container | 4-5 Quarts
16″ Container | 5-6 Quarts
18″ Container | 6-8 Quarts
20″ Container | 8-10 Quarts
24″ Container | 10-12 Quarts

*Note: If you’d like to start with a larger centerpiece like a Petitti-grown Color Your Garden 8″ plant, it takes up about the same amount of space as 2 quarts.