Tropicanna cannas, with their height, tropical flair and season-long color, are an excellent choice for container gardens. That’s why this easy-care, versatile plant stars in my latest two Growing Wisdom gardening-how-to videos, “How to Build the Perfect Container Garden featuring Tropicanna canna” and “Easy Tips for Growing Plants in Containers.”
Here’s a breakdown of the tips I shared in the videos above:
Prepare your pot
- Lightweight, synthetic pots mimic the look of heavier materials that dry out quicker (i.e. wood, metal, clay).
- Drill a hole into the bottom of your pot if it doesn’t already one.
- A layer of rocks at the bottom will improve drainage and stop soil from falling out.
- To save money on container soil, stack small, upside-down plastic pots within your container until they’re slightly above the proper planting depth. Cover with landscape fabric, then soil before planting.
- Fill pot halfway with lightweight potting mix for containers and work in a slow-release, granular fertilizer.
- Loosen the roots of each plant with your hands before potting.
- If you put the tall plant in the center, the filler can go all the way around that and the spiller all the way around that. If you put the tall plant in back, the filler can go in front of that and the spiller in front of that.
- A layer of mulch on top helps hold in moisture.
Think in threes
An easy way to ensure a pleasing design is to use three kinds of plants: a thriller (the “wow” factor, often the tallest plant), a filler (fills the center of the container) and a spiller (tumbles over the container’s edge).
For my thriller, I chose Tropicanna Gold (green leaves with gold stripes) and Tropicanna Black (burgundy-black leaves). For my filler, I chose purple celosia; and for my spiller.
Here are some other combinations . . .
Echo or contrast colors, textures
When it comes to mixing and matching plants, it’s about echoing or contrasting colors and textures. For instance, the broad, flat, ovate or lanceolate leaves of Tropicanna cannas differ from the fleshy rosettes of echeveria, yet the two go together, since they’re both burgundy. In the videos, I contrast the dark burgundy canna or echeveria with either a white petunia or purple celosia. The color of your pot is also part of your palette.
Monitor and maintain
- Plants in pots dry out quicker than plants in the ground, so check the moisture level daily (I like to do it in the cool of the morning) by sticking your finger 2 to 3 inches into the soil. Only water if it’s dry. On hot days, you may need to water again in the afternoon.
- For optimum growth and performance, plants also need liquid fertilizer.
- To grow a successful organic container add worm castings, compost or fish emulsion to your containers. Adding fertilizers with live microbes will also help keep your soil healthy throughout the season.
- Deadheading prolongs the display and keeps plants looking tidy. Remove dead blooms and yellow or brown leaves and shred for mulch.
- Be sure not to remove side-shoots below the first set of flowers; these become subsequent blooms.
- Remember: Most cannas don’t need staking unless their in a high-wind area.
Tropicanna cannas are hardy from zones 7 to 11, so those in Zone 6 and below will need to bring them in for the winter. You can keep them in a cool (not freezing) area like a basement. If you don’t have such an area, you can store the rhizomes in warmer spaces in peat moss. Click here for more tips on winter care of tender bulbs.
Do you have a great container garden recipe? We’d love to hear it.
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