Flowers and Plants
Warm Up Mild-Winter Gardens With This Cheery Australian Native
Outback cassia’s colorful branches and foliage bring color to the cool-season garden
There are few shrubs that add color to cool-season landscapes, which makes outback cassia (Senna oliogophylla) a wonderful addition in regions with dry climates and mild winters. From the yellow flowers to the green leaves and maroon branches, there is no shortage of colorful interest, regardless of the season. Flowering begins in midwinter and continues into spring, adding a warm, cheery element to gardens. This cassia species enjoys a spot where it can grow in full sun, and thrives in drought-tolerant landscapes.
Distinguishing traits. Glossy green foliage, made up of 1-inch-long leaves, grows along maroon stems, creating a lovely contrast of colors throughout the year. Golden flowers appear in the middle of winter when not much else is in bloom, adding much-appreciated winter interest to the landscape. Flowering lasts until midspring, followed by green seedpods that turn maroon.
This Australian native does best in dry climates and needs very little maintenance other than pruning in late spring, after flowering has ceased. Avoid pruning later in the year, which would reduce the next season’s flowering. For the best appearance, allow outback cassia to grow to its natural rounded shape, and avoid formal pruning.
This Australian native does best in dry climates and needs very little maintenance other than pruning in late spring, after flowering has ceased. Avoid pruning later in the year, which would reduce the next season’s flowering. For the best appearance, allow outback cassia to grow to its natural rounded shape, and avoid formal pruning.
How to use it. This large shrub looks great when arranged informally in a staggered row in groups of three or five, anchoring the corner of a landscape. Outback cassia also makes a nice informal hedge or background plant for pool areas.
To create a dramatic contrast of winter color, plant it alongside ‘Valentine’ bush (Eremophila maculata ‘Valentine’), whose red blossoms will add a colorful feast for the eyes. Santa Rita prickly pear (Opuntia santa-rita) is another plant that adds cool-season color contrast.
For colorful interest year-round, team it with shrubs that bloom during the warm season, such as Baja fairy duster (Calliandra californica), desert ruellia (Ruellia peninsularis) and Texas ranger (Leucophyllum frutescens).
To create a dramatic contrast of winter color, plant it alongside ‘Valentine’ bush (Eremophila maculata ‘Valentine’), whose red blossoms will add a colorful feast for the eyes. Santa Rita prickly pear (Opuntia santa-rita) is another plant that adds cool-season color contrast.
For colorful interest year-round, team it with shrubs that bloom during the warm season, such as Baja fairy duster (Calliandra californica), desert ruellia (Ruellia peninsularis) and Texas ranger (Leucophyllum frutescens).
Planting notes. Outback cassia needs full sun and can even handle exposures with reflected sun. While its needs are minimal, it must have well-drained soil. Avoid planting in humid climates, where it can struggle.
For gardeners in the eastern U.S.: Consider planting American senna (Senna hebecarpa, zones 4 to 8), which is native from Wisconsin and Illinois east to southern New England and south to Georgia and Tennessee.
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Discover other beautiful yellow flowers
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For gardeners in the eastern U.S.: Consider planting American senna (Senna hebecarpa, zones 4 to 8), which is native from Wisconsin and Illinois east to southern New England and south to Georgia and Tennessee.
More
Discover other beautiful yellow flowers
See more ways to improve your garden
Common names: Outback cassia, bloodbush, buttercups
Origin: Native to Australia
Where it will grow: Hardy to 20 degrees Fahrenheit, or minus 6.7 degrees Celsius (USDA Zone 9; find your zone)
Water requirement: Low
Light requirement: Full sun
Mature size: 5 feet tall and wide
Benefits and tolerances: Drought-tolerant
Seasonal interest: Golden flowers appear in the middle of winter and last until midspring
When to plant: Spring, fall or winter