Coleus Care Guide: How to Grow Coleus in Your Garden

A member of the Lamiaceae family, coleus plants are tender tropicals whose foliage varies widely in shape and color. While coleus plants bloom with white or blue flowers, most breeders focus on the unique colors and patterns of the square coleus leaves by pinching off the flower spikes to help the plants focus energy on their leaves.

Coleus plants can reach their full size of approximately six inches to three feet tall and one to three feet wide in a single season. The colorful leaves of coleus plants range from one to six inches in length. There are two types of coleus plants:

1. 1. Upright coleus: Upright coleus, also called mounding coleus, are often used in border edging or mass plantings. They are known for their compact, easily controlled growth habits. Varieties of upright coleus include kiwi fern and fishnet stockings.
2. 2. Trailing coleus: Plant trailing coleus in hanging baskets or containers. Trailing coleus often have smaller leaves than uprights. Cultivars of trailing coleus include ‘Red Trailing Queen’ and ‘Trailing Rose’.

Given the large number of cultivars of coleus on the market, there is one to fit every kind of garden:

1. 1. ‘Alabama Sunset’: Also called ‘Bellingrath Pink’, reaches approximately 16 to 26 inches in height. It has red-pink leaves and does best with full sun.
2. 2. ‘Diablo’: This type of coleus reaches approximately 34 inches at full growth. It is known for ruffled red leaves with dark centers and grows best in a garden with shade and part sun.
3. 3. ‘Thumbelina’: This kind of coleus is extremely small. Its leaves are approximately one inch in length, and it stands at about six inches tall. This unique plant has green and burgundy leaves.
4. 4. ‘Gold Brocade’: This coleus is recognizable for its bold leaf color. It has gold leaves speckled with purple and red at stands 18 inches at full height.
5. 5. ‘Wasabi’: ‘Wasabi’ coleus grows best in a garden that allows for full sun. It is known for its serrated, chartreuse-colored leaves.
6. 6. ‘Lime Time’: ‘Lime Time’ coleus is large, standing up to 36 inches at full height. It thrives in shade and part sun, and its leaves are lime green.
7. 7. ‘Fishnet Stocking’: This type of coleus reaches 24 to 36 inches in height and 12 to 16 inches in width. It grows best in partial to full shade and will thrive as a bedding plant or in hanging baskets. Its green leaves feature maroon veins.

You can grow coleus plants from coleus seeds or cuttings. While it’s best for them to receive at least part shade, they will still grow quickly in conditions of full sun or full shade. Follow these tips for planting and maintaining your coleus plants:

• Plant after the last spring frost. Coleus should only be planted outside after the last frost date. Otherwise, it will be in danger of frost damage. Wait for evening temperatures of above 60 degrees Fahrenheit before planting coleus outdoors.
• Plant coleus in rich, loose soil. This plant enjoys soil that’s consistently, but not overly, moist. Soil that is too damp can lead to disease. Amend the soil with compost before planting coleus, and mulch the area around the plant to help the soil retain moisture. If soil remains dry for too long, the plant’s growth will slow, and its leaves will begin to turn brown. Keep in mind that too much mulch may promote rot or mealybugs, so do not allow it to touch the coleus stems.
• Water coleus plants consistently. Water coleus plants twice a day when the weather is hot.
• Make sure the plant receives enough sunlight. In some environments, coleus can thrive in full sun or full shade. However, if your area is especially hot, you must ensure it receives some afternoon shade. The amount of sunlight the plant receives will impact its appearance, with morning sun and afternoon shade allowing it to produce more colorful foliage.
• Propagate your coleus plants. Take cuttings in early fall, and root them in water over the winter. They will be ready to be planted outdoors in the spring.
• Protect coleus plants from pests and disease. Coleus plants are generally unbothered by pests or diseases, but they do become more susceptible to fungal disease in cold, damp conditions. You can protect indoor coleus plants from mealybugs, whiteflies, aphids, and spider mites by misting the plants with horticultural oil. Protect outdoor coleus plants from deer by spraying them with a repellent or by growing them in hanging baskets.
• Overwinter coleus plants indoors. To protect your coleus plants from winter frost, you can dig them up and bring them indoors during the coldest months. Ensure that you get as much of the root system as possible when removing them from the ground, and plant them in pots with well-draining potting soil. Another option is to take cuttings from your healthy plants to grow new plants for the next season.

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