The plant hails from Burma (Myanmar) and is winter hardy in the United States in USDA hardiness zones 10 through 11.
This compact plant attains a height and spread of 1′ to 3′ feet.
The plant’s botanical name – Strobilanthes dyerianus (stroh-bil-AN-theez dy-er-ee-AN-us) comes from the Greek word, strobilos (cone) combined with the Greek word anthos (flower).
‘Dyerianus’ honors the late 19th century/early 20th-century botanist named Sir William Turner Thiselton-Dyer.
He was the director of the Royal Botanic Gardens of Kew from the late 1800s to early 1900s.
Persian Shield Strobilanthes Dyerianus Care
Size & Growth
In a frost free climate, it is possible to grow Persian Shield to heights of 4′ feet tall and 4′ feet wide.
Outside of USDA hardiness zones 10 and 11, it is unlikely to grow taller or wider than 3′ feet.
Flowering & Fragrance
It is unusual for this plant to flower outside of its native land. In very warm, humid settings, the plant may bloom during the autumn or the wintertime.
Persian Shield plant is a seasonal bloomer that occasionally produces small, five-lobed violet flowers.
The flowers are individually quite small. However, they grow in cone-shaped bunches and are quite appealing.
It is the shape of these inflorescences that earned the plant its common name, Bermuda Conehead.
Although the flowers are attractive and even showy, the main draw of this plant is it’s stunning silvery/iridescent purple foliage.
The purple leaves of these foliage plants are oval and somewhat lance-shaped. The base color is a deep green infused with a flush of silvery purple.
The undersides of leaves are very deep purple. Leaves may reach 8″ inches in length.
Light & Temperature
Persian Shield does well in a wide variety of light settings ranging from partial shade to full sun.
For the best foliage color, keep the plant in a partially shaded area.
If you’re in a cooler climate, the plant may need full sun in the summer for optimum color.
When overwintering keep the plant as a potted or container plant in a bright and sunny location.
Some sources say that this plant is hardy from USDA zones 8 to 11.
However, it may die back late in the autumn in zones 8 and 9.
In these zones, it’s a good idea to cut it back before cooler weather arrives and cover it during the coldest months.
Take cuttings as insurance, just in case your plant does not grow back from the roots.
Watering & Feeding
This plant has moderate watering requirements but does need consistently moist soil.
When growing as a houseplant, it’s a good idea to establish a weekly watering schedule to keep the soil evenly moist.
Fertilize several times a year (3) using a slow-release plant food. Follow packaging instructions carefully.
Soil & Transplanting
Persian shield dyerianus appreciates a very rich, organic soil.
It likes even moisture at all times, but cannot stand in water. Well-drained soil is essential.
To keep Persian Shield as a houseplant, use high quality of potting soil rich in organic matter. The container needs plenty of drainage holes.
Grooming & Maintenance
Very little maintenance is required during the growing season.
However, preparing Persian Shield for overwintering and keeping them sheltered through the winter can be something of a challenge.
These plants need very little care and grooming.
They may be left to grow to their full height and width, or pinch them back to promote more compact and bushy growth.
You may also like these plants from the family Acanthaceae:
How To Propagate Strobilanthes Dyerianus Persian Shield
Although the same plant grows from one year to the next by bringing it in as a houseplant through the winter and taking it back out in the summer.
It is really preferable to propagate new plants by taking cuttings annually.
As the Persian shield matures, they develop woody stems. This reduces the brilliance of the coloration and the quality of the leaves.
Take stem cuttings to propagate from new growth on overwintered plants to produce new ‘shields’ to set out in the spring.
Another option is to take cuttings from outdoor plants late in the summer to grow new ones to overwinter.
Persian Shield is easily propagated by cuttings.
- Cut off stems a couple of inches long.
- Remove the lower leaves and place the cuttings into fresh water.
- Change the water every day or two until you see roots forming.
- Once the cuttings have several sets of good roots
- Plant them into their own pots or containers and care for them as mature plants.
Strobilanthes Persian Shield Pest or Diseases
This plant does not experience any serious disease or insect problems.
When overwintering plants, be on the lookout for spider mites.
Even though Persian Shield likes consistently moist soil, take care not to let it stand in water or root rot will ensue.
Is Strobilanthes Shield Considered Toxic or Poisonous?
Generally speaking, members of the Acanthaceae family are non-toxic.
Anecdotal evidence suggests that the sap of Persian Shield may be irritating to skin.
Is The Persian Strobilanthes Considered Invasive?
There is no indication that this plant is invasive, even in very conducive climates.
Suggested Strobilanthes Persian Shield Uses
Persian Shield naturally grows in warm and humid settings.
In areas such as Florida, it can be kept as an evergreen perennial.
Throughout the United States, Persian Shield can be used as a summer annual in the garden.
It’s a great choice for a rain garden and for persistently damp, shady areas.
Persian Shield also makes an excellent houseplant year-round in any climate.