How to Successfully Grow Coleus from Seed

Choosing and Preparing Seeds

coleus seeds selection

Choosing and preparing seeds is an essential step in growing healthy and vibrant coleus plants. Before you start, you need to ensure that you have the correct seeds, as not all coleus seeds are created equal. Also, you need to prepare the environment for the seed to thrive. In this article, we will discuss the different types of coleus seeds and how to choose and prepare them for planting.

Types of Coleus Seeds

types of coleus seeds

Coleus seeds come in different varieties, and each breed can affect the appearance and growth of the plant. The commonly used types of coleus seeds are:

  • Straight Species Seed: These are the most natural and wild form of coleus. They come in various colors, sizes, and shapes and are the true reflection of what the plant would look like in nature.
  • Hybrid Seed: These are the most commonly used seeds and are bred to provide unique color and leaf patterns. They are engineered to maintain a certain consistency in appearance, growth, and size.
  • Elites/Clones: These are the highest quality coleus seeds from a specific cultivar. They are carefully selected and treated to ensure the plant’s properties are maintained.

Choosing Coleus Seeds

choosing coleus seeds

When looking for coleus seeds to buy, there are several things to keep in mind:

  • Choose viable seeds: The seeds’ quality will determine the success rate of your coleus plant. Ensure the seeds are fresh and viable. Check the label to confirm the seed’s viability, seal the seeds’ envelope in a plastic bag, and store it in a cool and dry place.
  • Determine your desired plant’s characteristics: Before buying coleus seeds, check the plant’s shape, size, and color to ensure they match your desired outcome.
  • Verify the seed’s germination requirements: Different coleus seeds have different germination requirements, like lighting, temperature, humidity, and soil type. Ensure the seed’s label indicates the requirements, or ask about them from the vendor.

Preparing Coleus Seeds for Planting

planting coleus seeds

After choosing and buying coleus seeds, it’s essential to prepare them for planting. The preparation process will help eliminate weak, damaged or infected seedlings and ensure the viability of the remaining seeds. Here are some preparation steps:

  • Clean the seeds: Use a fine sieve or strainer to clean the seeds to remove unwanted debris or seeds that float.
  • Soak the seeds: Soak the seeds in room temperature water for 24 to 48 hours to help speed up the germination process. Also, you can add a drop of dishwashing soap to the soaking water to help break down the seed’s natural coating.
  • Plant seeds in a sterile mix: Fill containers with fresh sterile mix, plant seeds ¼” deep, and cover the container with plastic wrap to keep humidity levels high. Keep the containers at 70°F with bright indirect light until germination.
  • Thin the seedlings: Once the seedlings have reached a few centimeters high, remove the weakest seedlings to allow the strongest seedlings to grow better.

Overall, choosing and preparing coleus seeds for planting is crucial in growing healthy and beautiful coleus plants. Make sure to select viable seeds, determine your desired plant’s characteristics and verify the seed’s germination requirements. Also, ensure to clean the seeds, soak them, plant them in sterile mix, and thin the seedlings.

Optimal Growing Conditions

Optimal Growing Conditions

Coleus is a popular ornamental plant that is easy to grow from seeds. With the right care and growing conditions, it can grow quickly and provide a great pop of color to your garden or indoor space. Here are some tips to ensure optimal growing conditions for your coleus seeds.


When it comes to light, coleus plants prefer bright, indirect light. Direct sunlight can burn and dry out the leaves, while too little light can cause the plant to become leggy and lose its vibrant colors. If you’re growing coleus indoors, place it near an east, west or south-facing window where it can get plenty of bright but filtered sunlight. If you’re growing it outdoors, choose a spot that receives partial shade, particularly in the afternoon when the sun is at its strongest.


Coleus can adapt to various types of soil, as long as it’s well-draining. The ideal soil pH for these plants is between 6.0 and 7.5. If your soil is heavy, add some sand to improve drainage. If it’s very light, add peat moss or compost to help retain moisture. If you’re growing coleus in containers, use a good-quality potting mix that’s rich in nutrients, but also light and well-draining.


Coleus plants like to be kept consistently moist, but not waterlogged. It’s best to water them when the top inch of soil feels dry to the touch. When watering, make sure to saturate the soil and let the excess water drain away. Avoid getting water on the leaves, as this can cause spotting and disease. In hot and dry weather, coleus plants may need to be watered more frequently.

Temperature and Humidity

Coleus is a tropical plant that thrives in warm temperatures and high humidity. Ideally, the temperature should be between 60-75°F (15-24°C). If the temperature drops below 50°F (10°C), the plant may stop growing and become damaged. Coleus is also sensitive to dry air, so if you’re growing it indoors, misting it regularly or placing a humidifier nearby can help maintain the desired humidity levels.


Coleus plants are heavy feeders and require regular fertilization to maintain healthy growth and vibrant colors. Use a balanced, water-soluble fertilizer every two to three weeks, or a slow-release fertilizer that can be mixed into the soil at the beginning of the growing season. If you’re using a liquid fertilizer, make sure to dilute it to half strength to avoid burning the leaves.


Growing coleus from seeds is a great way to produce many plants at once. Sow the seeds in a seed tray or pot filled with seed-starting mix, and keep them moist and warm until they germinate. Once the seedlings have developed their first true leaves, transplant them into individual pots or containers with well-draining soil. Wait until after the last frost to transplant them outside. You can also propagate coleus from stem cuttings, taking care to remove the lower leaves and dip the cut ends in rooting hormone before planting them in moist soil.

In summary, coleus plants need bright, indirect light, well-draining soil, consistent moisture, warm temperatures and high humidity, regular fertilization, and proper propagation techniques to thrive. By providing these optimal growing conditions, you can enjoy a lush and colorful coleus plant for years to come.

Sowing and Transplanting Seedlings

Sowing and Transplanting Seedlings

If you want to grow coleus from seed, you need to start by sowing the seeds. This step is critical because it determines the future of your plants. The following steps will guide you through the process of sowing and transplanting seedlings:

Step 1: Choose the Right Time

The most important thing to keep in mind when sowing and transplanting coleus seedlings is the best time to do it. You need to sow the seeds at the right time to ensure the best results. The best time to sow coleus seeds is in early spring, shortly before the last frost is expected.

Step 2: Prepare the Soil

Next, you need to prepare the soil before sowing the seeds. You can use any potting soil mix that is suitable for starting seeds. Make sure that the soil is moist and loose but not dripping wet. Coleus seeds need loose soil to germinate successfully, but they also require consistent moisture to grow properly.

Step 3: Sow the Seeds

After preparing the soil, you can now sow the seeds. Coleus seeds are small, so you need to be careful not to sow them too deep or too close together. Use a toothpick or your finger to make a small hole in the soil, and then drop a seed into the hole. Cover the hole with soil, and press it down lightly.

Make sure that you sow the seeds evenly and leave plenty of space between them. Coleus seeds usually take around 7-14 days to germinate, so be patient.

Step 4: Transplant the Seedlings

When the seedlings are about 2-3 inches tall and have two or three sets of true leaves, they are ready to transplant. You can transplant them to individual pots or a larger container with well-draining soil.

Gently lift the seedlings from the soil using a small spoon or your fingers. Be careful not to damage the roots. Transplant each seedling into a pot filled with fresh soil, and water them thoroughly. Keep the soil evenly moist, but avoid over-watering, as it can cause root rot.

If you prefer to grow coleus in your garden, you can transplant the seedlings outdoors after the last frost. Choose a location with well-draining soil and partial shade. Space the plants at least 12 inches apart to allow for growth.

Step 5: Care for Your Coleus Plants

After transplanting your coleus seedlings, it’s important to give them the proper care to ensure healthy growth. Here are some important care tips:

  • Water your coleus plants regularly, but don’t over-water them. Coleus plants need consistent moisture, but they don’t like to sit in water.
  • Fertilize your coleus plants regularly with a balanced fertilizer to promote healthy growth and vibrant foliage.
  • Pinch back the tips of your coleus plants regularly to encourage bushy growth and prevent legginess.
  • Watch for signs of pests or diseases, and treat them promptly to prevent damage to your plants.
  • Enjoy your beautiful, colorful coleus plants!

Following these steps will help you to grow healthy and vibrant coleus plants from seed. Sowing and transplanting seedlings can seem daunting, but with the proper care and attention, you’ll be rewarded with beautiful, colorful plants that will brighten up your home or garden.

Providing Adequate Care and Maintenance

Coleus Care and Maintenance

Coleus is a low-maintenance plant that doesn’t need much attention when it grows. However, that doesn’t mean that it doesn’t need any care. Like all plants, it requires specific conditions to grow healthily and beautifully. By providing your coleus with proper care and maintenance, you can ensure that it thrives.


Coleus Need Watering

Coleus plants are thirsty and require regular watering. Ensure that the soil is moist but not waterlogged. Water your coleus once a week during spring and once every two weeks during the summer. Overwatering can cause root rot, so it’s essential to maintain the correct balance. If your coleus starts to wilt, it’s a sign that it’s not getting enough water, and you need to step up your watering schedule.


Coleus Fertilizer

Coleus plants are not heavy feeders, but they require nutrients to thrive. Fertilize your coleus once or twice a month with a balanced fertilizer. Stop fertilizing in the winter because the plant doesn’t grow actively during that time. Over-fertilizing can cause excessive growth, which can reduce leaf color. Fertilizing also helps to improve the soil quality and aids in the plant’s overall health.


Coleus Needs Light

Coleus loves bright but indirect light. Consider placing your coleus plant near a window that receives lots of natural light. However, ensure that the sunlight doesn’t hit the plant directly as it can damage its foliage. If you’re growing your coleus indoors, consider providing artificial light in the form of fluorescent bulbs. Keep the light on for 12-14 hours a day during the growing season. If your coleus is not getting enough light, its growth will be stunted, and its colors will fade.


Coleus Pruning

Coleus plants can grow quite large, so it’s essential to prune them regularly to maintain their shape and size. Pruning will also encourage bushy growth and prevent legginess. Ensure that you pinch back the tips of your coleus stems frequently to encourage fuller growth. Use a pair of clean, sharp scissors or pruning shears to remove any dead or yellowing foliage. Remember to prune your coleus after it has bloomed, to encourage regrowth and promote healthy foliage.

Pest and Disease Management

Coleus Pests

Coleus plants are susceptible to whiteflies, spider mites, and mealybugs. These pests suck the sap from the plant, causing yellowing leaves and stunted growth. Use insecticidal soap to control these pests or move the plant to a new location. Also, be sure to check your plant regularly for signs of fungal growth, which can cause leaf drop. Provide proper ventilation to the plant to prevent it from getting fungal diseases. If your coleus does get infected, remove the infected leaves and make sure to disinfect the pruning shears or scissors before using them on other plants.

By following these simple care and maintenance tips, you can grow beautiful and healthy coleus plants from seed. Remember to provide the plant with adequate light, water, and nutrients to ensure it thrives. Happy planting!

Troubleshooting Common Issues

Troubleshooting Common Issues

While growing coleus from seed can be an enjoyable and straightforward process, problems may arise. Here are some common issues that you may face while growing coleus from seed, along with solutions to resolve them:

Poor Germination Rate

Poor Germination Rate

Poor germination rates can be due to several factors, including poor soil quality, low humidity, and incorrect temperature. Coleus seeds need a temperature of around 70°F (21°C) to germinate, so ensure that the soil’s temperature stays consistent.

You can add some vermiculite to the soil to help retain moisture without increasing the risk of fungal infections. Ensure you keep the soil moist, not watery, and ensure it stays warm. In some rare cases, the seeds may be too old, which may cause poor or no germination. So, make sure you buy your seeds from reputable vendors.

Yellow Leaves and Stunted Growth

Yellow Leaves and Stunted Growth

If your coleus plants begin to yellow and wilt, check for pests such as spider mites or whiteflies. Pests can cause severe damage to the plant, and their treatment should be taken immediately.

Coleus plants are prone to root rot, which can be caused by overwatering or poor drainage. Reduce watering intervals to keep the soil moist but not soaked. If drainage is a problem, consider repotting the plants while ensuring the pot has drainage holes.

Leggy Plants

Leggy Plants

Leggy plants are coleus plants that have thin, weak stems and have grown too tall in search of light. To stop leggy growth, ensure your plants receive sufficient light by placing them in a bright, well-lit area.

If necessary, rotate the plants weekly to balance their exposure to light. Pinching off the tip of the plant’s stem encourages the growth of side branches and forces the plant to become bushier. Pruning overgrown stems will help to shape the plant and, in turn, encourage a bushier growth habit.

Faded Leaf Colors

Faded Leaf Colors

Faded leaf color can be caused by exposure to direct sunlight for extended periods, resulting in color loss and fading of the leaves. Coleus thrives in bright but indirect sunlight, so it’s best to keep them in well-lit but shaded areas.

The temperature of your growing environment may also affect the intensity of the plant’s color. Coleus prefers a warm environment, but temperatures that are too high or too cold may cause the plant’s color to fade. Ensure that the environment stays consistent in terms of both temperature and light.

Mottled and Spotted Leaves

Mottled and Spotted Leaves

If you notice mottled or spotted leaves on your coleus plants, it could be due to fungal infections such as leaf spot or powdery mildew. Fungal infections thrive in cool and humid conditions and can be treated by pruning any infected leaves and spraying with neem oil or a copper-based fungicide.

Ensure that the soil drainage is good to prevent water from standing and causing fungal infections. Additionally, avoid overhead watering and instead use a watering can to deliver water at the soil level.

Growing coleus from seed can be an exciting and rewarding experience. It’s a relatively easy process, and with proper care, you can enjoy a beautiful and vibrant garden. If any issues arise, take the necessary actions promptly to ensure your plants stay healthy and thriving.