How to Grow and Care for Coleus Indoors

Coleus plants are petite and herbaceous, commonly grown as houseplants for their bold, colorful foliage in shades of green, pink, maroon, purple, and more. They grow relatively quickly and can live for multiple years when kept inside. Vibrant and low-maintenance, these plants are a popular choice.

When growing coleus, keep in mind that these plants are toxic to people and pets.

Can You Grow Coleus Inside?

Growing coleus inside is ideal for many, because these plants cannot survive the winters outdoors in most regions, perennial only to USDA hardiness zones 10 and 11. Coleus is comfortable in most indoor lighting conditions and doesn't require much space, rarely growing to much more than a few feet tall and wide. With proper watering, coleus plants thrive in typical indoor surroundings.

How to Grow Coleus Indoors

Sunlight

Coleus plants love bright light, though it's best to avoid direct midday sunlight, which can scorch the delicate leaves. Your best bet is to find a windowsill or other spot in your home that gets direct sunlight in the morning and bright, filtered like in the afternoon. It will be a bit of a balance—too much sun can fade the plant's colorful foliage, but too little can lead to less-than-vibrant hues.

Temperature and Humidity

Coleus plants prefer an average temperature above 60 degrees Fahrenheit in the summer. In winter, they can tolerate a slightly lower temperature, though they should always be kept about 50 degrees Fahrenheit.

High humidity is also preferred by the coleus, so try keeping your plant in a typically-humid room of the home, like the kitchen or bathroom. Otherwise, you can increase humidity by lightly misting the plant a few times a week (especially if it's looking droopy) or investing in a small space humidifier.

Watering

It's important that you keep the soil of your coleus plants continuously moist throughout the year, though you can typically reduce your watering cadence in the winter months. A coleus plant's soil should never be allowed to dry out. To check and see if your plant is ready for a shower, stick your finger into the surface of the soil about two inches deep—if the soil you touch is dry, it's time for watering.

Fertilizer

Though not a true necessity, coleus plants can benefit from feeding each spring with slow-release pellets, or weekly during their growing season with liquid fertilizer.

Pruning and Maintenance

Overtime, coleus plants can become somewhat leggy, especially if they aren't receiving enough light. To combat this, prune the plant by pinching off leggy growth. This should result in more growth toward the base of the plant and a more bushy look.

Container and Size

When choosing a container or pot for coleus plants, plastic or ceramic may be best so that the soil does not dry out quickly. Terracotta could also be used with soil that retains some moisture. Either way, a drainage hole is crucial. Regarding size, select a pot that is only a few inches larger than the plant's rootball at the time of potting.

Potting Soil and Drainage

Plant your coleus in a soil mixture that is moist but well-draining. Typically a generic potting mix will suffice just fine, but if you notice that you're having issues with too-damp soil, you can amend your mixture with a bit of perlite or vermiculite to aid in drainage.

Potting and Repotting

A large coleus plant can reach between two to three feet in height. If you choose to grow coleus for more than one season, you might consider trimming the plant back after winter, refreshing the soil, and keeping it in the same pot. Typically, coleus plants will only grow as large as their current pot allows, and will not outgrow their space. That being said, if you desire a larger plant, all you need to do is replant your coleus in a bigger pot and it will grow to accommodate its new container.

Moving Coleus Outdoors for the Summer

Though coleus plants grow well indoors, they will do their best outside. Depending on where you live, you can move these plants outdoors for summer, giving them a boost before they come back inside for the colder months.

Considerations

Coleus plants will not be happy when the outdoor temperature is below 60 degrees Fahrenheit, and they will likely perish in a frost. They can also be harmed by temperatures above 100 degrees Fahrenheit. Be sure to consult the weather forecast, and don't move your coleus outside until the temperatures are reliably in a comfortable range.

Regarding location, coleus plants do best in partial sunlight, though it's crucial to slowly let your plant slowly adapt to outdoor sun conditions, especially after many months indoors. Start by giving your plant an hour or two of sunlight per day, and slowly work up to a full day outside.

Keep in mind that you will also have to water your coleus more often once it's outdoors, as it will likely grow faster and both the sun and the wind will cause the soil to dry out quickly.

When to Bring Coleus Back Inside

When nighttime temperatures start to dip into the 50s, you should consider bringing your coleus inside. A few nights under 60 degrees Fahrenheit won't kill the plant, but a hard frost might. Look over your coleus carefully for outdoor pests before bringing it back into your home.