The Persian shield is a rarity: a foliage plant that features shiny, purple, and striking leaves. The leaves are almost metallic in their hue. The plant does flower, and in fact, will flower year-round under good conditions, but it's best to remove the flowers as they appear to prevent the plant from becoming leggy. It's also best to pinch off the growing shoots to keep the plant compact and bushy. While they aren't especially complicated in their growth requirements, it's best to aggressively trim the plant down to size. In their native environment, the most popular variety of Persian shield will easily achieve four feet. These plants display particularly well with other brightly colored foliage plants, such as coleus or begonia.
Light: Persian shield thrives in dappled light to full sun. It partly depends on your latitude and the strength of light. Plants exposed to too much sun will not develop their full leaf color, so if they look washed out, move the plants to a shadier place.
Water: Persian shields need regular moisture throughout the year but not tremendous amounts. Drainage is important for a well-grown plant. Do not allow them to sit in soggy trays.
Soil: A rich, peat-based potting soil with excellent drainage is beneficial.
Fertilizer: Feed with a weak liquid fertilizer throughout the growing season.
Persian shield can be propagated by seed, but it's unlikely you'll get seeds in an indoor setting. Instead, propagate by stem tip cutting during repotting time. To take a cutting, choose new growth and use a rooting hormone for an increased chance of success. Place cuttings in seed-starting soil and locate in a warm, humid place until new growth emerges.
The Persian shield is a relatively fast-growing, woody shrub that is grown as a perennial in warmer regions or as a returning perennial in colder areas. Indoors, the idea is to keep the plant to a manageable size instead of letting it grow to its full capacity. To accomplish this, repot younger plants annually until they reach their maximum size then repot every other year. Root prune older plants also to keep them small enough to display inside. If your plant becomes leggy, take stem cuttings and discard the mother plant.
The Strobilanthes genus includes about 250 herbs and shrubs throughout Asia. Cultivated species range from smaller plants that are used as ground cover to the most commonly seen shrubby plants. The most common species and the one known as Persian shield is usually the S. dyeranus, which features eight-inch leaves and can grow to about four feet in height. The leaves are silver and purple with iridescent markings on the top that can range from green to purple to silver and even pink. Leaf margins are typically scalloped.
The Persian shield is not a particularly difficult plant to grow, providing you can give it the warmth and moisture that it needs. In colder conditions, the plant will drop leaves, and if you live in a place with colder winters, you might want to cut the plant down to the soil level to overwinter. It will grow back from the soil level provided it was not frozen. The main challenge with Persian shield is likely to be keeping the plant a suitable height for indoors.
Persian shield plants are not particularly susceptible to pests but can be affected by mealybugs, aphids, and mites. Signs of infestation include tiny webs on plants, clumps of white "powdery" residue, or visible insects on the plant. Treat infestations as soon as possible to prevent them from spreading to the rest of your collection.