Alternanthera (Joseph’s Coat plant) is a genus of more than 200 species of tender perennial and bushy annuals grown for their colorful foliage as garden plants and indoor plants.
This plant belongs to the Amaranthaceae family and is native to subtropical and tropical areas of South America and Central America.
The genus Alternanthera has various popular species, including:
- Alternanthera Ficoidea
- Alternanthera Dentata
- Alternanthera Brasiliana
The common names for Alternanthera include:
- Purple knight
- Joseph’s coat
- Calico weed
- Calico plant
- Little ruby
Alternanthera Quick Care Tips
- Botanical Name: Alternanthera ficoidea ‘Party Time’
- Common Name(s): Josephs Coat Plant, Purple knight, Joseph’s coat, Calico weed, Calico plant, Joyweed. Little ruby
- Synonyms: –
- Pronunciation: Al-ter-NANTH-ur-uh
- Family & Origin: Amaranthaceae family, native to South America and Central America
- Growability: Easy to grow
- Grow Zone: USDA zones 10-11
- Size: Can grow up to 12” inches tall and wide
- Flowering: Produces small white flowers in summer
- Light: Full sun to partial shade
- Humidity: high humidity levels, around 50–60%
- Temperature: Prefers warm temperatures between 60-85°F
- Soil: Well-draining soil
- Water: Regular but light watering
- Fertilizer: Fertilize with a balanced liquid fertilizer every two or three weeks during summer
- Pests & Diseases: Can be susceptible to slugs, aphids, caterpillars, spider mites, and aphids. Watch for root rot if overwatered.
- Propagation: Can be propagated by cuttings or by seed
- Plant Uses: Used as a colorful foliage plant in borders, containers, and as a groundcover. Can also be used as an indoor plant.
Joseph’s Coat Care
Size and Growth
This plant has an upright spreading habit of growth, reaching maturity around 12” inches tall and spreading 12” inches wide, a typical growth habit among its species.
The burgundy foliage of this plant remains dense to the ground.
The foliage color ranges from green to burgundy color, but the leaf color is a striking shade of dark purple.
It also has the tendency to arch over containers.
Flowering and Fragrance
The unique feature of Joseph’s Coat plant is the purple to green leaves instead of its flowers.
The bloom time of the purple knight is short. The white flowers are tiny and formed in axillary and terminal spikes.
Depending on the cultivars, the green leaves may be blotched with brown, copper, yellow, red, orange, or purple.
It adapts easily to its environment but works best as annuals as backdrop landscaping, edging, or as a summer bedding plant.
Light and Temperature
Joseph’s Coat Plant thrives best under full sun but also grows well when placed in partial shade.
For intense foliage color, place it under the full sun. The USDA hardiness zones of this plant are 10 – 11.
The ideal daytime temperature for this plant ranges from 80° to 85° degrees Fahrenheit and a nighttime temperature from 62° to 65° degrees Fahrenheit.
Watering and Feeding
The Alternanthera plant prefers regular but light watering.
Make sure to water the plant enough to avoid letting the soil dry out completely.
The new plants need frequent watering for the initial weeks. But once established, this plant is heat and drought-tolerant.
Watering must be adjusted as per the soil type and weather.
Water lightly for clay soil as they sustain more moisture, but water more in sandy soils as they need increased humidity.
They thrive in high humidity levels, around 50–60%.
This plant doesn’t require extra fertilizer, as a high amount of feed damages the plant.
However, if your Joseph’s Coat looks weak, feed it some balanced liquid food during summer.
You can also use a balanced liquid fertilizer, such as a fish emulsion, once every two or three weeks during summer.
For outdoor plants, feed your potted Alternanthera plants once every two months.
Soil and Transplanting
The Alternanthera Ficoidea plant is used in most soil types as long as it’s well-draining.
Add some organic matter, like garden compost, peat moss, or manure, to enhance soil drainage.
Applying a thick mulch around the root zone during the growing season is also recommended to conserve soil moisture.
Grooming and Maintenance
Joseph’s coat plant is relatively low-maintenance as long as it grows in well-draining soil in full sunlight.
It’s best to prune this plant to maintain its compact size.
Ideally, grow the plant after the last frost has passed.
When growing Joseph’s Coat in a greenhouse, ensure it stays under full light and is appropriately watered throughout the growing months.
During the winter season, place this plant in a spot with good ventilation and water sparingly.
When growing in a container, frequently water during the dry, hot season.
Regularly pinching off its growing tips gives this plant a more neat and formal look.
Be sure to feed it lightly every two months when grown as ground plants and every two to three weeks as container plants.
How to Propagate Alternanthera
The propagation of the purple knight is done using cuttings or seeds.
When growing it from seeds, it is best to prepare the seeds in germinating mediums for around five weeks before transferring them into the garden.
It is ideal to transplant or transfer the plant outdoors during the night when the temperature consistently stays at 60° degrees Fahrenheit (15° C) or above.
The cuttings should be taken during the late fall season and root them in a mixture of sand and vermiculite or perlite.
For growing this plant as perennial, it is best to divide its clumps during the spring season.
Alternanthera Pest or Diseases
Most of the issues faced by the purple knight are easily preventable by selecting the right location and soil type.
The plant will develop rot and lose its foliage color when growing in a location that is not well-draining.
Make sure to grow this plant under the full sun in a well-draining spot for its striking burgundy foliage.
The lankiness and unsightly shape are avoided with regular pruning and pinching during its growing season.
Joseph’s Coat Plant Uses
This plant works well when used as a ground cover or bedding plant in borders, garden beds, and along pathways and sidewalks.
This makes an excellent houseplant when growing in hanging baskets and outdoor containers.
Its striking floorage color adds appeal to any dull corner and adds a bold touch to tabletops, desks, and other such surfaces.
Because of this plant’s ornamental features, Joseph’s coat plant provides a wonderful background and canvas of foliage for larger thriller plants to stand out and makes a lovely filler for spiller-thriller-filler’ container combination.
Its unique textured and colored leaves also go well with almost every houseplant.