Persian shield care guide

Persian shield has long, pointed leaves that shimmer in metallic purple and silver, with dark green veins and deep red undersides. It comes from Myanmar. In cold climates, it is often grown outside as a summer plant in pots. Indoors, it needs bright light, steady water, and moist air to keep its color.

Light

Give it bright indirect light. An east window is ideal. A few hours of soft morning sun deepens the purple.

In low light, the purple fades to a dull green-gray. Hot afternoon sun bleaches and scorches the leaves.

Water

Water when the top 2 cm (1 in) of soil is dry. Water until it drains, then empty the saucer. Keep the soil moist, not soggy. In winter, it needs water less often.

It wilts hard when it is thirsty, then perks up within hours of a drink. Do not let it wilt often. Each time, it drops a few lower leaves. Read how to tell if a houseplant is overwatered or underwatered.

Soil and potting

Use a rich, well-draining houseplant mix.

It grows fast in spring and summer. Repot every spring, one size up. See how to repot a houseplant step by step.

Humidity and temperature

It needs moist air. Aim for 50% humidity or higher. In dry air, leaf edges brown and crisp, and spider mites move in. A humidifier helps.

Keep it between 18 and 24°C (65 and 75°F), and above 15°C (60°F). Cold drafts make it drop leaves.

Feeding

Feed monthly in spring and summer with a balanced liquid fertilizer at half strength. Skip feeding in fall and winter.

Pruning

Pinch off the stem tips often. Each pinch makes two new stems below it. This keeps it bushy instead of tall and bare.

The best color is on young leaves. Older plants get woody and lose some shimmer. Start fresh from cuttings every year or two.

Propagation

Cut a stem tip 10 cm (4 in) long. Pull off the lower leaves. Root it in a glass of water or in moist mix. Roots form in one to two weeks.

If you grow it outside in summer, take cuttings in late summer. Root them indoors to keep it through winter.

Problems

What you see	Most likely cause
Wilting	Thirst
Brown, crispy leaf edges	Dry air
Purple fades to green-gray	Not enough light, or an older plant
Bleached, scorched patches	Too much direct sun
Tall, bare stems	It needs pinching, or more light
Leaves drop	Cold drafts, or it dried out
Fine webbing under leaves	Spider mites

Pests

Spider mites are the most common pest, most of all in dry air. Whiteflies, aphids, and mealybugs show up too. Check under the leaves every week. Rinse the plant in the shower to knock pests off.

Pet safety

Persian shield is not on the ASPCA list of toxic or non-toxic plants. Most sources treat it as non-toxic to cats and dogs. The sap may irritate sensitive skin, so wash your hands after pruning.

Varieties

Persian shield is sold as one species, Strobilanthes dyeriana. Its color varies with light and age, not variety.