Coleus Care Guide: Vibrant Colors Made Easy

Coleus, renowned for its dazzling array of colorful foliage, is a gardener’s favorite for adding bold splashes of color to shaded areas and sunny spots alike. With endless patterns and hues to choose from, this low-maintenance foliage plant is perfect for borders, garden accent plants, outdoor containers, and indoor potted arrangements. This guide provides all of the details necessary to grow and care for Coleus successfully.

What Are Coleus?

Coleus is a tropical, tender perennial (in USDA Zones 10 and 11) often grown as an annual in cooler climates and is a very popular houseplant. Valued for its striking, multi-colored and patterned foliage, Coleus comes in a kaleidoscope of colors, including reds, yellows, purples, and greens with whimsical leaf designs. 

History and Origin

Native to Southeast Asia and the Pacific Islands, Coleus has been cultivated for centuries for its ornamental foliage. It gained popularity in Victorian gardens during the 19th century and remains a staple in modern landscaping and indoor gardening. Selective breeding advancements have produced a wide range of sun-tolerant and shade-loving varieties.

Choosing the Right Variety

Coleus varieties are divided into two primary categories based upon their light requirements.

• Shade-Loving Varieties
  • Thrive in partial to full shade.
  • Are ideal for woodland gardens, shaded patios, and under large trees.
  • Will thrive in indoor environments with limited light.
• Sun-Tolerant Varieties
  • Tolerate full sun without fading or scorching.
• Are well-suited for sunny borders and exposed container arrangements.
• Will enjoy that southern, eastern, or western window when indoors.

When selecting Coleus, consider

• Color Scheme: Choose hues and patterns that complement your garden design, or that area rug in your living room.
• Growth Habit: Select upright varieties for borders or trailing types for hanging baskets and containers. For indoor planting, choose the best growth habit that fits your decorating needs.

Planting Options

You can grow Coleus from seeds, cuttings, division, or nursery plants.

From Seeds

• When to Start: Sow indoors 8 to 10 weeks before the last frost date.
• Advantages: Coleus seeds are affordable and allows you to grow a wide range of varieties for a minimal cost.
• Temperature: Coleus seed germination will occur with consistent temperatures between 70° and 75°F. If you keep your home cooler, investing in a seed-starting mat or heating pad will ensure a higher germination rate.

From Cuttings

• When to Propagate: Take cuttings in late spring or summer.
• What to Propagate: You must use a whole stem to propagate, not just a leaf. Select a stem with several sets of leaves, preferably 4 to 6 inches in length.
• How to Propagate: You can use a rooting medium or water. Rooting hormone is a good investment to ensure a quickly growing and strong root system. Rooting in water gives you the added benefit of being able to see the root growth and ensure its health before planting in soil.
• Advantages: Propagating in water or soil is quick and ensures an exact replica of the parent plant. Propagating will increase the number of Coleus plants you have in your garden and home. This is also a great way to create gifts for friends and family.

From Division

• When to Divide: Divide your Coleus plants in early to mid-spring so your plants have plenty of time to fill in before summer. If you have a mature plant that has outgrown its container or that you would prefer to be smaller because it may be crowding other plants in your garden, you may want to divide that plant.
• How to Divide: Water well the day before to loosen the soil and hydrate your plant to better prepare it for division. If in the garden, dig around the root ball, staying 6 to 8 inches away from the center of the plant. If dividing from a potted plant, lift the entire plant out of the pot. Gently shake off any excess dirt and tease apart the root tendrils into as many clumps as you’d like.
• How to Replant: After dividing, plant the divisions at the same depth, gently tamping the soil as you fill in the hole or add soil to your pot. Water gently to allow the soil to fill in air pockets and then water again. Keep it evenly moist until new growth appears, then return to your regular watering schedule.

From Starter or Nursery Plants

• When to Plant: Transplant outdoors after all danger of frost has passed. If your Coleus appears rootbound and it will be a potted indoor plant, then choose a larger container to transplant to.
• Advantages: Purchasing already established plants provides instant, colorful, foliage impact.

Soil Preparation

Healthy soil is vital for vibrant and lush Coleus growth.

• Type: Use well-draining, fertile soil in the garden or in the pot. When potted, ensure there are drain holes in the bottom of the pot and use a drain tray.
• Amendments: Add compost or organic matter to improve soil fertility. This will also improve drainage in the garden. To determine the drainage quality of your garden soil, you may want to perform a percolation test, especially if you know you have heavy or clay soil, or if plants are not doing well in a specific spot.
  • The Soil Percolation Test can be used to check how fast…or slow your garden soil drains. This involves digging a hole 12” wide and 12” deep. Fill it with water and let it drain out completely. Once the water has drained, within the next day or two, fill the hole again. You will be measuring how fast, or slow the water drains from your soil.
    • Fast-Draining Soil is probably mostly sand and will drain in under 3 hours.
    • Well-Draining Soil is the sweet spot. Between 30 to 70% of the water will drain in 3 hours. If the hole is half full of water, your soil is perfect.
    • Slow-Draining Soil will be comprised mostly of clay and will be 80 to 90% full after 3 hours

Sunlight and Temperature Requirements

• Light Requirements: Provide bright, indirect sunlight for shade varieties and full sun for sun-tolerant types. For indoor plants, the shaded varieties will prefer indirect sunlight, while the sun-tolerant varieties will enjoy a bright, sunshiny window.
• Temperature Range: Coleus thrives in temperatures between 70°F and 85°F. Avoid planting outdoors when temperatures drop below 60°F.
• Frost Sensitivity: Coleus is not frost-hardy. Wait until all danger of frost has passed before planting outdoors. You can dig them up and transplant to a pot to move them indoors during the winter.

Planting Coleus

Whether planting in the ground or containers, follow these steps for success:

Spacing

• Upright Varieties: Space plants 12–18 inches apart.
• Trailing Varieties: Space 18–24 inches apart for adequate room to spread.

Planting Depth

• Plant at the same depth as they were in their nursery pots or propagation trays.

Watering and Fertilization

Watering

• Frequency: Keep the soil consistently moist but not soggy. Water more frequently during hot, dry weather.
• Method: Water at the base of the plant to avoid wetting the foliage, which can lead to fungal diseases.

Fertilization

• Type: Use a balanced, water-soluble fertilizer. Miracle-Gro^® is ideal for indoor or outdoor plants.
• Frequency: Feed every 4 to 6 weeks during the growing season, following the manufacturer’s directions.

Pruning and Maintenance

• Pinch Back Tips: Regularly pinch back the tips to encourage bushier growth.
• Remove Flowers: Unless you’re saving seeds, remove flower spikes as they appear to redirect energy into foliage production.
• Saving Seeds: Allow the flowers to grow to maturity, waiting for the flower to fade and dry out, which will produce small seed pods. Wait for the seed pods to turn brown and start splitting. Harvest the tiny, dark seeds from inside and place them in an envelope or dry container. If you have more than one variety, be sure to label the seeds. Store the seeds in a cool, dry place.
• Mulching: Apply a layer of mulch around the base of the plant to retain soil moisture, deter weed growth, and regulate temperature. This is not needed with indoor, potted Coleus plants.

Pest and Disease Management

Although Coleus is relatively pest-resistant, occasional issues may arise.

• Pests: Watch for aphids, whiteflies, and spider mites. Use insecticidal soap or neem oil to control infestations. This is rare on indoor plants unless you have moved them from the garden or have brought other plants into the house that may have an infestation.
• Diseases: Prevent powdery mildew and root rot by ensuring good air circulation and avoiding waterlogged soil. You will also want to avoid overhead watering, water at the soil level.

Overwintering Coleus

Since Coleus is frost-sensitive, there are steps you can take to preserve your plants through the winter.

1. Bring Indoors: Potted plants can be brought indoors and placed in a bright, sunny window for sun-tolerant varieties, or provide indirect light indoors for shade-tolerant coleus plants. You can also gently dig up your garden plants, repotting for indoor display.
2. Take Cuttings: If you prefer not to repot, you can propagate cuttings in water or soil to grow new plants for the following season.
3. Divide: If your plants are large and fully mature, you can divide them to more manageable sizes to repot them for the indoors. You can transplant these plants back to the garden after all danger of frost has passed.
4. Treat as an Annual: In cooler climates, and for those who just don’t have the luxury of the time to ‘winterize’, Coleus is often treated as an annual and replaced each spring.

Companion Planting

Coleus pairs beautifully with other plants, enhancing garden aesthetics and indoor potted arrangements.

• Ferns and Hostas: These plants complement Coleus’ bold foliage with softer, different textures and richer colors of green.
• Begonias: Begonias add vibrant blossoms, interesting texture, and architectural interest alongside colorful foliage.
• Grasses: Use ornamental grasses to contrast Coleus’ lush, broad leaves, especially in gardens or large indoor containers.

ProTips for Container Gardening

Coleus thrives in containers, making it ideal for patios, balconies, and indoor spaces.

• Containers: Use pots with adequate drainage holes.
• Soil Mix: Opt for a well-draining potting mix with added organic matter.
• Arrangements: Combine upright and trailing varieties for a dynamic display.

Common Problems and Solutions

• Leggy Growth: Ensure your Coleus is receiving adequate light and pinch back new growth on the stems to promote bushier growth.
• Leaf Scorching: Protect shade-loving varieties from direct sun.
• Drooping Leaves: Check for underwatering or overwatering and adjust as needed.

With its vivid foliage, adaptability, and versatility, Coleus is an excellent choice for gardeners of all skill levels. Whether used as a bold accent in borders, a centerpiece in containers, or a bright addition to your indoor spaces, Coleus offers endless possibilities for creativity and enjoyment.

Add a splash of color to your garden or home this season with the vibrant and adaptable Coleus—it’s sure to steal the show!