Grown best in a shadier area, as these often grow under the cover of trees, dappled sunlight is just fine.
People in hot desert environments where the sun is blindingly hot should also plan on going for partial shade conditions when growing this outdoors. At the very least, ensuring the plant has afternoon shade during the hottest part of the day is wise.
If your plant is getting too much sunlight, it won’t develop that vibrant, iridescent purple tone, and you should move it somewhere shadier.
Growing your Persian shield as a houseplant? If so, you’ll need a grow light or a sunny window to ensure your plant’s catching enough rays. You’ll also want to turn the plant regularly to ensure it doesn’t become leggy as it reaches towards the light.
Temperatures for this plant should remain above 60 degrees to maintain that brilliant coloration. While light frosts will cause the plant to die back, it may recover in the spring if it never got to hard frosts or freezing conditions.
Water and Humidity
Your royal purple plant will like having consistent, even moisture in its soil. Water when the top couple of inches of soil are dry, which indoors is often twice a week (and may be more often outside).
Indoor growers need to monitor their soil moisture regularly, especially throughout the winter months when we’re all running our heaters.
Persian shield does like to grow outside as well, but when doing that, be sure that the soil also remains consistently moist, and add mulch to keep the soil moisture from evaporating.
This is a high humidity plant — it likes damp air! To increase that, place your pot on top of a tray of pebbles and water. The water will evaporate and provide more humid conditions. Outdoor growers can set bowls of water next to their plants for similar effect.
As a tropical plant, your Strobilanthes dyerianus is naturally accustomed to rich soil filled with plenty of plant matter that retains water. To simulate this, you’ll want to opt for a rich and well-drained soil. Consider adding extra compost, vermiculite, or peat moss to help keep it moist.
The pH level should be between 5.5 and 7.5 for best growth.
These are extremely good as container plants, and most people grow them that way. However, they can work as bedding plants too provided that you’ve developed a well-drained planting location for them.
For most of the year, fertilizing should be done every two weeks with a half-diluted, low-NPK liquid plant food. Aim for one which is balanced NPK, as it requires the nitrogen to grow and the rest to develop healthy root structure and provide its brilliant color.
Slow down feeding as you move into the fall to once a month, and withhold fertilizer through the winter. Once the spring comes again, return to a regular 2-week pattern.
it’s easy to propagate from seeds or cuttings, but I find that cuttings work best.
Preparing your cutting is simplicity itself. Select a stem which is 6″ long and remove all but the uppermost leaves. Place the cut end into either a glass of water or some moist rooting medium of your choice. If using water, change the water daily. In rooting medium, keep it evenly moist.
Place your plant in a shaded location where it still gets some indirect light, and ensure that the humidity is kept up around the plant (a plastic bag placed overtop can help with this). It will develop roots in 2-5 weeks depending on the plant’s vigor and the season.
Many people seldom repot these Persian purple plants if they’re thriving, because they simply don’t need it. If your plant looks healthy and happy, then you’re doing just fine!
However, if you want to encourage your plant to expand in size, it’ll need more root space. Also, if it seems to be going through water very quickly, switching to a pot that’s 1-2 inches larger will add more soil and help retain more moisture.
If you do opt to repot, prepare your soil in advance and have it ready. You may wish to gently open up the roots of the plant if it seems to be a bit pot-bound, then replant at the same depth it was previously planted.
Try to avoid jumping drastically in pot size. A plant which was previously planted in a 4″ pot shouldn’t go up to a 12″ pot, as it’ll take forever for it to fill that much space.
Other than removing leaves that have died back, there’s little pruning that needs to be done.
Pinch back stems to encourage your plant to become bushier. This can be done at any time that it’s required.
Your plant can get leggy as it gets older, during the winter, or if it needs to be repotted. If pinching back does not discourage the leggy habit, consider repotting. For the winter months, pinch off flower stalks and occasionally pinch back excess stem growth. While optional, some report that trimming the plant back to a foot tall (leaving enough leaves for photosynthesis) at the end of winter encourages their plants to burst forth with new vigorous growth in the spring.