How to Grow Stunning Coleus Plants

There are lots of summer annuals like zinnias and geraniums that give you a beautiful display of flowers, but few plants can match coleus for its colorful and attractive foliage.

Coleus plants are very easy to grow and propagate. They look stunning in the garden but can also fill out containers and window boxes. When you see the wide range of textures, colors, and patterns coleus comes in, you won’t even notice the lack of flowers.

If you’re ready to add bright, bold foliage to your garden this year, here’s what you need to know about how to grow and care for coleus plants.

What Is Coleus?

Coleus (Plectranthus scutellarioides or Solenostemon scutellarioides) belongs to the mint family, although it won’t have the familiar fragrant smell. Plants have square stems that are distinctive of the mint family and extremely colorful leaves.

Although it can be grown as a perennial in USDA hardiness zones 10 and 11, coleus is grown as an annual in most regions and is extremely sensitive to frost.

The leaves are typically pointed and often ridged. There are over 600 varieties of coleus that come in many shades of green, red, burgundy, purple, pink, and yellow. Some varieties will have foliage that is a solid color, while others are variegated, striped, or splotched.

It’s hard to find a summer annual with more colorful leaves than coleus. Because of their wide variety, these plants fit into almost any garden and also work well in containers.

Coleus plants do bloom under the right conditions. Many gardeners consider the blue or white flower stems to be insignificant and clip them off. Others enjoy their subtle appearance.

Many varieties of coleus are compact, growing 6-12 inches tall. Others are larger and can grow up to three feet. There are also three forms of growth: upright, rounded, and trailing.

Coleus Varieties to Try

With all the options out there, you might have a hard time deciding which variety to try first! Garden centers usually have a pretty good selection, but buying seeds will give you even greater choice.

Things to consider when choosing a variety include mature size, texture/color, light requirements, and growth habit. Here are a few cultivars to get you started:

• ‘Dipt in Wine’– Very showy foliage that is crimson with a yellow center and lime green border. Grows 2-3 feet tall.
• ‘Fishnet Stocking’– This variety has light green foliage with purple to burgundy veins. Grows 2-3 feet tall.

Dipt in Wine is a bright and vibrant cultivar that has crimson to burgundy leaves, yellow centers, and lime green edges.

• ‘Black Dragon’– Very unique foliage, even for a coleus. Leaves are ruffled and a deep burgundy color. Plants need shade and grow 12-14 inches tall.
• ‘Pineapple’– Leaves are ridged and a golden yellow color with red and lime-green accents. Grows 1-2 feet tall.
• ‘Lime Time’– This variety has bright lime green/chartreuse foliage that goes well with dark purples and burgundies. Grows 2-3 feet tall.
• ‘Campfire’– Foliage is a unique and vibrant dark orange that looks especially stunning in mass plantings. Plants grow in both sun and shade and get 1-2 feet tall.
• ‘Japanese Giant’– This cultivar has unusually large leaves that are red and purple with bright green centers. Grows 2-3 feet tall.
• ‘Alabama Sunset’– This coleus has leaves that are sunset colors: red, orange, and yellow. Grows 2-3 feet tall.
• ‘Watermelon’– Leaves on this cultivar are shades of red and pink with bright green edges. Grows 1½ -2 feet tall.

Watermelon is another bright cultivar that has red and pink leaves with green edges. Colors will be either dark or more washed out, depending on how much sun the plants get.

• ‘Trailing Plum’– True to its name, this is one of the best trailing coleus varieties. Leaves are a variegated purple and love the sun.
• Wizard Series– If you only have a small space or pots to work with, these are compact cultivars that grow about 10-14 inches tall. You can get a single color or a mix.

How to Grow Coleus

Coleus is easily propagated from seed or by cuttings. You can buy a packet of seeds to start indoors in late winter. Or if you have access to a coleus plant, you can take some cuttings to grow your own.

Growing Coleus from Seed

Growing from seed gives you a lot more choice when it comes to variety, although you may not be able to get seeds for some of the newer hybrids that are mainly sold in nurseries.

You’ll want to start your seeds indoors about 10 weeks before your last average frost date. Fill up a seed starting tray with a good quality seed starting mix. Get the mix wet enough that it clumps together when squeezed but not to the point where it’s dripping.

Sprinkle your coleus seeds onto the soil. Gently press them into the soil mix, but don’t cover them because they need light to germinate.

Cover your trays with plastic domes if you have them, and set the trays somewhere that’s between 70-75°F. Make sure they get sunlight from a window, or place them under grow lights to germinate.

You can easily find coleus at your local garden center or nursery, but plants are also very easy to start from seed. Giving seedlings good air circulation and enough water as they grow will help give you healthy plants.

You should see tiny seedlings sprouting in 10-14 days. When this happens, remove the plastic domes, and make sure the trays are by a sunny window or under grow lights.

Keep the soil in your trays consistently watered as your seedlings grow, but avoid watering the leaves of your plants. Run a fan on your plants a few times a day to help prevent diseases that come from poor air circulation.

About a week before you plant to plant outside, harden your seedlings off by taking them outside during the day and bringing them back in at night.

Growing Coleus from Cuttings

If you have access to a mature coleus plant, one of the easiest ways to propagate it is by taking cuttings.

Cuttings can be taken pretty much any time of year, but for spring planting, taking them in the fall is best. You can let your cutting root and grow over the winter, and you’ll have mature transplants ready to go out in the spring.

To take cuttings, use a pair of scissors or garden clippers to cut off 4-6 inches of stem from healthy plants. Remove the bottom ⅓-½ of the leaves, and place the stems cut end down in jars of water. Make sure that there are no leaves touching the water.

Most coleus varieties root extremely easily in water, and you’ll see roots growing out of your cuttings in just a few weeks. Some of the larger and more exotic varieties are harder to root, so take multiple cuttings to give yourself a better chance of success.

Once your cuttings have developed a good root system, you can take them out of the jars and plant them in small pots.

Fill the pots with a moist potting soil mix. Separate the cuttings and plant one per pot. Water them in and let them grow by a sunny window or under grow lights until they can be planted outside.

Planting Coleus

Coleus is very sensitive to even the mildest of frosts. Plants should go outside only after all danger of frost has passed and the soil has warmed considerably.

They can go in containers more quickly than in the ground, since the soil in pots will be warmer. Try to let temperatures at least get consistently into the 60’s before planting.

Growing Conditions

Coleus plants will have different light requirements depending on the variety. Older cultivars mostly grow in part to full shade, but newer ones need more sun to keep their leaves vibrant.

Consistent watering is one of the biggest “secrets” to keeping coleus plants happy. This means you should plant them somewhere that’s easy to water or somewhere the soil doesn’t get extremely dry.

Check on the light needs of the variety you’re growing, but most will do best if they can get morning sun and some shade in the afternoon, especially in regions with hot summers.

Coleus will grow in average soil but does like to have consistent moisture, so don’t plant it anywhere that gets really dry (or anywhere that’s difficult to water). You can amend with compost before planting to help your soil retain moisture better.

One last factor to keep in mind is that plants will do best if protected from high winds. Coleus has succulent-like stems that will snap if blown around too much.

How to Plant Coleus

Once you’re sure all danger of frost and chilly weather has passed, it’s time to start planting!

Larger coleus plants will need to be spaced out anywhere from 1-3 feet depending on the variety. More compact plants can be planted closer together and look especially nice in mass plantings.

Depending on the look you want in your garden, coleus can be a specimen plant or planted in large groups for a stunning effect. Just be sure to plant after all danger of frost has passed.

Dig holes for your plants that are just slightly wider than the root balls. Gently remove the plants from their containers and loosen the root ball if it has wrapped around itself.

Place plants in the holes you have ready for them and fill in the holes with soil. You want the soil to just cover the top of the root ball and not bury the stem at all. Firm the soil around each plant with your hands to make sure they stay in place.

Water your new plants well and continue to make sure they have enough water for the first week or two after planting.

Planting in Containers

Coleus plants work great in container gardens and will either fill or spill out of pots, hanging baskets, and window planters.

Growing coleus in pots is a lot like growing it in the ground with a few important differences. You’ll still need to pay attention to the light requirements for the variety you’re growing and place containers where they’ll get enough sun and/or shade.

When choosing a container, keep in mind the color of the coleus you’re planting. Pick colors that will complement the foliage of the variety you have.

Coleus can grow even in relatively small containers, but it’s best to avoid terra-cotta pots. Plants like consistently moist soil, and the porous nature of terra-cotta means the soil will dry out quickly. If you really want to use clay pots, line them with plastic before adding soil.

You can plant containers that are only filled with coleus, or you can mix them in with other plants. They work well with plants that trail and with those that flower.

Even though coleus doesn’t like to dry out, it’s still important to have good drainage. Make sure your containers have drainage holes or drill a few in yourself.

Fill your containers with a high-quality potting soil that preferably has a good amount of organic material in it or a slow-release fertilizer already added. Plant your coleus either by itself or mixed with other plants that need similar growing conditions.

Coleus Care

Perhaps the biggest care requirement of coleus is to make sure plants stay watered through hot and dry spells. Don’t allow the soil to dry out at any time, but don’t overwater so that it gets soggy. Coleus in containers will need watered more often than plants in the ground.

Mulch can be used around plants to help keep moisture in the soil and to keep weeds down. Apply mulch so that there’s an inch or two of space between it and the stem of your plants.

You may or may not need to fertilize coleus in the ground depending on your soil fertility. However, if your soil is on the poor side, you can apply a liquid fertilizer every month to keep plants happy.

Mulch helps to keep moisture in the soil, but it can also cause rot and other issues if the weather is damp. Apply a light layer and keep the mulch away from plant stems for the best results.

If you’re growing in containers, a slow release fertilizer mixed in with the potting soil is often the best choice. You can also fertilize every two weeks with a liquid plant feed.

Coleus can be regularly trimmed to keep its appearance neat and to help plants bush out. Unless you like how they look, flower spikes can be snipped off when they appear so that all of the plant’s energy can go into its beautiful foliage.

How to Overwinter Coleus

Although it’s a tender annual, coleus plants are easy to overwinter so that you don’t have to buy more in the spring.

To do this you can choose to simply pot your plants up and keep them as houseplants over the winter. This works better for the more compact varieties but can be tricky if you have very large coleus plants.

Give each plant its own separate pot and place the coleus by a sunny windowsill in your house. Rotate plants every so often so that they get sunlight on all sides, and trim plants as needed to keep them compact.

A second method for overwintering coleus is to take cuttings in the fall so that they can root and grow over the winter months. This is the best option if you don’t have a lot of space inside for plants or if you have large coleus plants that won’t fit in pots.

To use this method, just follow the steps for propagating coleus from cuttings in the section on how to grow coleus.

Since coleus grows extremely well from cuttings, it’s easy to overwinter plants this way. Your cuttings will spend the winter months growing and putting down roots and will be ready to be planted outside in late spring.

Pests and Problems

Coleus plants usually aren’t bothered by many pests or diseases. If the growing conditions turn cold and damp, they may be susceptible to fungal disease like powdery mildew. Proper spacing is the best way to avoid this.

Indoor coleus plants may have problems with spider mites, scale, or mealybugs. You can control these pests with an organic spray or horticultural oil.

Outdoors, coleus plants are not the first choice for deer and rabbits, but they aren’t resistant, either. Your best option is to protect plants when they are small or spray a repellent.

What to Grow With Coleus

Designing with coleus is easy since they work well with a wide variety of other plants. Keep in mind that coleus plants can rarely take full sun, so plan to mix them with other part sun or shade plants.

Here are a few ideas:

• One of the best planting companions for coleus is more coleus. Try combining contrasting colors like lime green and burgundy to really make a statement or plant upright and trailing varieties in a container.
• Because plants can grow anywhere from 10 inches to over 3 feet, where you plant coleus depends on the variety you’re growing. Taller cultivars can make good specimen plants, while more compact varieties work well as edging plants or mass plantings.
• Take advantage of the fact that coleus likes to grow in shade and use it in containers to brighten up dingy corners. Those with yellow or lime green leaves will especially brighten up shady spots.
• Use trailing varieties as a “spiller” for containers. Combine them with plants that flower to get both colorful blooms and bright foliage.

Once you find how easy it is to grow coleus and how much color they bring to your garden, you’ll be sure to plant it year after year.

Even though it’s already low maintenance, you can make growing coleus practically hands-off by using a self-watering pot. That will give you more time to relax and enjoy your colorful plants!