The polka dot plant is an eye-catching little plant with brightly variegated leaves that stand out against most other foliage. The most common polka dot plants feature leaves with a pink base color and green spots. But there are several spotted or mottled varieties with purple, white, red and deeper colors and brighter contrast, so the plants pop even more. These plants are not especially difficult to grow, but because they are native to warm climates, many gardeners treat them as annuals and replace them with new plants each year. They’re best planted in the spring. They also can be grown in containers as houseplants. They have a moderate growth rate and remain relatively small once mature, especially when grown indoors. They are not considered invasive plants; however, they have a vigorous growth rate in Australia, where they are a weed and have become invasive.
Warm temperatures and humidity are key to growing polka dot plants. Expect to water regularly unless you get sufficient rainfall. This plant also needs regular feeding throughout the spring to fall growing season.
Polka dot plants bloom sporadically, typically during the summer, with small lilac or pink-colored flowers on spikes. Pinch off these flower spikes to keep the plant’s energy focused on growing its vibrant foliage.
When grown outdoors, polka dot plants like a spot with some shade. Pick a planting site that’s not too bright, or else you can expect the foliage colors to fade, lessening the plant’s ornamental value. Bright, indirect light is ideal indoors, such as from an east- or south-facing window.
Polka dot plants prefer organically rich soil with good drainage. An all-purpose organic potting mix is typically suitable for these plants. Mix in some pumice or perlite to improve soil drainage.
These plants like a moderate amount of moisture in the soil at all times. Avoid letting the soil completely dry out, which can cause the foliage to wilt and make the plant struggle to survive. Never let the soil become soggy, which can cause root rot and kill the plant. Water the plant when the top half-inch of soil has dried out. Give enough water to moisten the soil evenly. You will need to water container plants more frequently than in-ground plants. Slightly reduce watering in the winter and resume your routine once growth picks up again in the spring.
Temperature & Humidity
Polka dot plants are only hardy in USDA growing zones 10 and 11, preferring temperatures between 70-80 F. They should be planted outside in the spring after the threat of frost has passed and brought inside if you plan to overwinter them well before the first frost of the fall. These plants like humid conditions, preferring a minimum humidity level of 50 percent. If you need to raise the humidity, you can mist your plant’s leaves or place its pot on a tray filled with pebbles and water as long as the bottom of the pot isn’t touching the water.
Feed container plants with an organic fertilizer designed for houseplants once a month during the warm growing season. These plants are heavy feeders. If planting in-ground, mix a layer of compost into the soil each spring.
Polka dot plants tend to get leggy. You’ll need a pair of clean, sharp scissors or pruning shears to keep the plant from developing long, lanky branches. To promote a bushier growth habit, cut or pinch back the top two leaves on each stem weekly. Actively trimming can help the plant to grow healthier and more vigorously. Although flowers sound nice, it’s best to clip them when they start appearing to extend the growing season of your polka dot plant. The flowers aren’t as ornamental as the leaves anyway. The plant will die off or enter dormancy once it has finished flowering.
Potting & Repotting
If a plant outgrows its container, it becomes pot bound or root bound. Its roots have nowhere to grow. A sure sign your plant has outgrown its pot is when the roots start growing out of the drainage holes. The best time to repot a polka dot plant is in the spring after its dormant period.
Gradually increase the plant’s pot size. The new pot should not be more than two inches wider and no more than two inches deeper than the old pot. Too large a pot encourages the roots to focus on growing below the soil line, which is not good for the plant’s upward growth.
Since this plant is a tropical plant, it will not survive frosty weather. Before the first frost, you can cut stems from the plant, root them indoors in a small potting container or jar of water. If kept outdoors in a container, bring these plants indoors to a partially sunny indoor spot. In the spring, you can replant it in the garden after the threat of frost is over.
Common Pests & Diseases
Common pests that enjoy polka dot plants are mealybugs, aphids, spider mites, thrips and blackfly. Typical diseases associated with polka dot plants are root rot, leaf-spot diseases, rust, southern blight, and powdery mildew. Telltale signs of these bug infestations or disease include foliage that’s discolored, leaves that have holes or otherwise appear unhealthy and small bugs moving on the plants.
How to Get Polka Dot Plant to Bloom
This plant flowers in late summer or early fall. The shortening of daylight hours tells the plant that the growing season is coming to a close, encouraging its flower growth. Its small lilac or pink-colored racemes or flower stalks are insignificant and not known for their scent or appearance. When flowers emerge, it triggers plant to begin to go dormant. So, in most cases if you want your plant to last longer, it’s best to cut or clip off the flowers as they begin forming.
Polka dot plants are relatively easy to grow once you get their growing conditions right. Here are the most common problems and some potential solutions.
Curling Leaves or Leaves Loosing Their Color
Curling leaves and fading leaf color are typically caused by too much sun. It needs bright, indirect light to maintain its color. But, it needs to be kept out of hot, direct sunlight. If it’s in a container, move it to a shadier spot. If it’s in-ground, think about giving it some cover.
Leaves Turning Brown or Drooping
Insufficient water and humidity can cause the polka dot plant’s leaves to turn brown or start drooping. Also, too much sun can burn the leaves. Hard water and overfertilization are other reasons for a polka dot plant’s leaves turning brown. Adjust your humidity or watering habits to see if you can revive the plant.
Leaves Turning Yellow or Dropping Off
Overwatering causes yellowing of the plant’s leaves. Soggy soil causes the yellowing of the leaves and leaf drop. Overwatering can also lead to other severe problems like root rot and powdery mildew. If you notice leaves yellowing, reduce the amount of water you give the plant and make sure you’re using potting soil with good drainage.
Are polka dot plants easy to care for?
Polka dot plants are easy to maintain and propagate. It can sometimes be difficult getting its growing conditions perfect, but once established, it’s usually good to go.
How fast does polka dot plant grow?
These plants have a moderate growth rate, although they tend to get picky with their growing conditions and tend to slow down their growth rate if they aren’t perfect.
How long can polka dot plant live?
Polka dot plants usually complete their life cycle within a year. But, you can prolong their life by propagating stem cuttings at the end of the growing season.
Information courtesy of TheSpruce.com