Coleus Care

Our Coleus Plants: All of the Coleus sold by Rosy Dawn Gardens are propagated from cuttings. We do not sell seed-grown varieties. Our growing method uses a lightweight substrate in a biodegradable sleeve. This provide us with robust plants and the highest cutting success rate we have ever seen. This growing method has the additional advantage of being compact and lightweight, which helps keep our shipping costs as low as possible. Our Coleus plants are ready to plant into pots and there is no need to remove the fiber sleeve as the roots will grow through it. Before planting in areas that receive a lot of sun or wind, make sure that your Coleus have a chance to develop a good root system. The root-balls with which they arrive with might not be able to provide the Coleus with enough water and nutrients to survive extreme outdoor conditions.

Most plants that we ship are single or multi-stemmed and between three and nine inches in height, depending on the cultivar. Coleus cultivars vary widely in height, leaf shape, and habit. Some Coleus are small and grow very slowly, sometimes taking months to grow just a few inches in height. Others root rapidly and bolt out of the gate with vigorous growth. We try to indicate in the catalog descriptions when a plant is small or slow-growing, so please read carefully before ordering.

Please note: We grow and ship husky starter plants ready to pot up and grow on. They are not full grown plants!  Before exposing your new Coleus to sun or wind they will need to be potted and grown on in a sheltered location until their root system is more developed. See "How to 'harden-off' Coleus" below.

When Your Plants Arrive:  When you receive your order from Rosy Dawn Gardens, carefully unpack each plant and inspect it for any damage that may have been caused by shipping. Please notify us within 72 hours of any defects that you consider out of the normal range for plants that have spent the last few days in a closed box. Remove the plastic sleeve from each root ball, and make sure your new plants receive water and fresh air upon arrival. Pot your Coleus plants immediately, and keep the plants out of wind and direct sun until they have hardened off. If you are unable to immediately put your new plants into soil please place them in a shallow waterproof container such as a cake pan or deli container until they can be planted. Keep the root balls moist, but do not allow your plants to stand in water as this could promote rot and disease. Holding Coleus in this manner for more than one or two days could negatively impact the health of your plants, so please plant them as soon as possible.

Planting your new Coleus: Your new Coleus plants should be planted in a good quality soil mix as soon as possible after arrival. If it will be a while before you will be able to place your new Coleus plant in its permanent pot it should be planted in a 4" pot and grown on until transplant time. If you are planning on planting your Coleus directly in the ground, it will be beneficial to first plant them in a 4" pot and allow them to develop a larger root system before asking them to fend for themselves out in the elements. A week or two of this preparation will pay off in faster growth and happier plants. The sooner your plants are planted in soil the faster they will expand their root systems and reach their full potential! If your Coleus are delivered before it is safe to place them outdoors (see "How to harden-off Coleus" below) then you must provide them a well-lit and warm spot indoors or in a greenhouse.

For their permanent home, a single Coleus plant will do well planted in a 6"-8" pot, while three or four Coleus may be planted in a 10"-12" (or larger) pot. All pots should have drainage holes. The soil mix should be high quality, airy, and well-drained, with lots of organic material. A time-release fertilizer for annual plants is highly recommended. Other products you may find useful are soil additives such as crystals that swell up into a jelly when water is applied. They are excellent for helping to keep Coleus hydrated on hot days. They store up to 400 times their weight in water and acting as a reservoir during dry periods. Coleus can also benefit from root stimulating products that add mycorrhizae to the soil.

How to "harden-off" Coleus: After potting your Coleus, place them outdoors everyday for 3-4 hours in full or partial shade in a wind-sheltered location. Gradually increase the time outdoors every day, and by the end of the first week you should be able to gradually begin to acclimate them to their permanent location (if it differs from where they have been previously held). A temporary windbreak or sun protection should be offered for a time if the Coleus are planted in an exposed location. Regular daily watering of exposed Coleus is crucial to their survival. Close attention should still be given to the amount of heat, cold, sun, and wind your Coleus receive for at least two more weeks after hardening off and protection should be available at any time during the summer if inclement weather or sudden cold snaps threaten your plants.

Caring for your new plants: All Coleus are tender and cannot survive freezing temperatures. It is best not to place them outside for the season until they have been hardened off and the average overnight low temperatures stay above 60 degrees. This might be a few weeks after your last average spring frost date. Even if there is no frost, nights in the 40's can damage your Coleus! Planting your Coleus outdoors while the nights are still cool may result in slow or stunted growth and an increased chance of fungal diseases caused by cool, wet soil. Your new plants from Rosy Dawn Gardens have been greenhouse grown, so it is important that they be "hardened off" before you place them outdoors. Planting your Coleus out into sun, wind, and/or hot temperatures before they have been properly acclimated can harm them and cause wilting and leaf damage. Direct sun and wind can be very damaging to tender young Coleus, so begin by potting them up and allowing them to develop a good root system. This step is especially important if you will ultimately be planting your Coleus directly into the ground. The larger their root system is at planting the better they will do.

Sun or Shade? In the tropical parts of the world where Coleus grow naturally, they are generally found it high shade or dappled shade. We find that some sun in the morning and protection from noon and afternoon sun is optimal for bringing out the best color, but not everyone has those perfect conditions. Coleus can be surprisingly adaptable as long as they are not allowed to get too dry. The amount of light your Coleus plants receive will affect their coloration, so the same variety of Coleus grown in two different locations in your yard may vary in appearance. A Coleus grown in full sun might create more pigmentation to protect itself from the sun and this may dramatically alter the look of the plant. Too much strong sun might result in sunscald, which can have a bleaching effect on the leaf and cause crispy edges and brown, thin spots on the leaves that might eventually become holes. Conversely, they might become "greened out" by the excess coloring produced by the plant to protect itself from the sun. Results will vary according to region. Full sun for our friends in Texas or Florida is much stronger than full sun for us here in Michigan! The most important thing to remember when growing Coleus in full sun is that they need a well-developed root system, proper soil preparation, and consistent watering to look their best.

Coleus have historically been considered a shade plant, and Coleus do grow well in dappled or partial shade, but no Coleus will do well in deep shade. Coleus are not mushrooms and a certain amount of bright light is necessary to maintain the proper level of pigment in the leaves. The deeper the shade, the more washed out the colors will be. Deep shade may also cause lanky, contorted growth as the plant stretches towards light, and damp soil may cause disease.

Most Coleus can take some sun, especially if it is morning sun, and several can tolerate full sun if properly acclimated. Experimentation is definitely in order to find which varieties do best in your particular conditions. The plants that are photographed for the Rosy Dawn Garden catalog are mature plants that have been grown in bright morning light with protection from the afternoon sun. Your Coleus may look different from our catalog photos depending on growing conditions.

Temperature: Coleus are native to some of the warmest climates in the world, but think tropical, not desert. Coleus are native to lands that lie close to the equator, which means the average temperature is 90 degrees Fahrenheit all year and there are no seasons other than monsoon seasons. There is absolutely no frost, so Coleus grow as herbaceous perennials. They can take an enormous amount of heat as long as they are grown in good soil that is kept evenly moist. In their native land they are usually found growing in high shade or dappled shade, and that makes the heat easier to bear. When planning where to place your Coleus keep in mind their tropical origin and try to duplicate it as closely as possible. While Coleus like it hot, they can do reasonably well in cooler temperatures as long as they don't fall lower than 60 degrees Fahrenheit. Temperatures in the 50s and 40s are survivable, but sustained cool temperatures will adversely affect the vigor and color of the Coleus and make it susceptible to disease. Freezing temperatures are deadly to Coleus and even a light frost will destroy the plant.

Watering and Fertilizing: Coleus prefer their roots to be in soil that is evenly moist but not soggy. The more your Coleus are exposed to sun and wind, the more often they will need to be watered. Daily or twice-daily watering may be necessary during very hot or windy weather, especially as the Coleus mature and develop a large leaf canopy. Coleus that have wilted will usually respond quickly when watered, but Coleus that have been repeatedly allowed to wilt will quickly show signs of wear and tear that make them less attractive: crispy edges, dry brown spots on the leaves, bleaching, and dull color. Drip irrigation is great for plants grown in pots or in the ground because it keeps the water off the leaves. Watering is best done in the early morning so the leaves have time to dry before the sun hits them. Coleus leaves should always be dry by the time darkness falls to decrease the chance of fungal disease occurring. Coleus do not show their best color when over fertilized, so fertilize with liquid fertilizer at half strength on a regular basis, or use a time release fertilizer (recommended). If you keep coleus indoors for the winter, fertilize less often during the winter months and increase fertilization frequency when the days begin to lengthen in the spring.

Pruning: Pinching the growing tips of your Coleus when they are young will increase branching and make your plant more bushy. Some Coleus plants will bloom, and the blooms may be pinched off or allowed to develop according to your personal preference. Keep in mind that a Coleus that is allowed to bloom heavily will lose vigor and beauty as it puts its energy into making seeds instead of growing beautiful leaves. It doesn't hurt Coleus to be pinched and pruned. In fact, it is often necessary to prune Coleus in mid-summer to help the plant keep its shape and freshen its appearance. A plant that is allowed to overgrow may cause its pot to topple or branches may snap under their own weight.

Mulch is recommended for Coleus grown in the ground to retain even moisture around the roots and prevent weeds. Do not use cedar mulch as the cedar oil can be toxic to coleus plants. Make sure the mulch is not touching the stems of the coleus as this could cause rot and give slugs cover while they gnaw at the stems of your coleus.

Coleus Pests: The best way to control pests is by regularly inspecting your plants and taking immediate action if you see signs of pests or disease. Individual insects or small colonies are eradicated far more easily and safely than large outbreaks. The most common pest of Coleus are mealy bugs, which look like little tufts of white fuzz on the stems, leaves, and leaf axils. They are very slow moving and can be eliminated by a cotton swab dipped in alcohol or by an insecticide spray (see below for recipe). Another pest you might encounter is whitefly, which are very tiny and fly out from under the leaves, especially when the plant is disturbed. Whiteflies are attracted to the color yellow, and a yellow sticky-trap (available in garden centers) can sometimes be used to identify and control them without pesticides. Aphids can also attack Coleus and can be treated by spraying them with water, wiping them off the Coleus, or spraying with an insecticide. Spider Mites can be identified by the tiny webs that form on the underside of leaves and the presence of poppy-seed sized red mites. Spider mites flourish when the humidity is low, and can be controlled by careful monitoring and cleaning of the leaves, increasing the humidity near the plants, or spraying the leaves with a soap spray. Fungus gnats are tiny black flies that hover near the soil. Fungus gnats are especially attracted to plants that have overly wet soil in an area of poor air circulation. They can be controlled by correcting any watering or air circulation issues that might exist and by adding a 1/4 inch layer of fine gravel (fine aquarium gravel or parakeet grit will do) to the top of the soil to prevent the adults from laying eggs. Slugs can damage Coleus by eating the leaves and stems. Commercial slug bait is available but you can make your own non-toxic slug traps using beer in a shallow saucer. A circle of diatomaceous earth powder around your plants can make a deadly barrier for slugs to cross as it will puncture their skin and cause them to dehydrate. Copper barriers will also create an uncomfortable situation for slugs.

Insecticide sprays may include insecticidal soap, neem oil products, pyrethrum sprays, or all-purpose houseplant or ornamental sprays available at garden centers. At Rosy Dawn Gardens we find that lady beetles, lacewings, and predatory wasps do a great job of policing our plants when they summer outdoors. We only use pesticides when the plants are in the greenhouse, and always try to use the least toxic types for our own safety and for the safety of our environment. A simple and effective soap spray can be made by mixing one teaspoon liquid soap to one quart water in a spray bottle. We use Dr. Bronner's Pure Liquid Castile Soap (it comes in several scents), but good results have been achieved with a relatively pure standard dish soap such as Ivory. To minimize the possibility of bad reactions use a soap with as few additives (perfume, dyes, detergents) as possible. Shake regularly while applying and cover all surfaces. Apply weekly if necessary. You can also experiment with making a mild tea with garlic, hot pepper, mint, or citrus peels and using that for the water base (after straining and cooling). Always test a small area of the plant with the spray for 24 hours before applying a home-made spray to the whole plant to check for possible adverse reactions, and avoid use on seedling or cuttings without prior testing. If you buy a prepared insecticide at a home store and garden center please read the ingredients and warnings carefully before you choose and follow the directions carefully. Keep your own safety and the safety of the environment in mind when choosing which chemicals to use.

If you can't control pests with the relatively harmless sprays listed above you may choose to use a systemic insecticide that you put in the soil. It will help with control of pests for several weeks at a time, but should only be used as a last resort and when you don't have any worries about children or pets ingesting your plants. Please: Only use systemic insecticides with Coleus grown in pots. We strongly discourage the use of systemic insecticides directly in the ground and on flowering plants such as roses. The nectar of flowers from plants treated with the systemic insecticide Imidacloprid (sold under many brand names) has been implicated in the death or illness of bees and in honeybee hive collapse syndrome, so please do not allow your Coleus to bloom outdoors when using systemic products. Please dispose of treated plants and soil as hazardous waste. Do not compost treated plants and soil as Imidacloprid can persist in the soil for quite some time.

Coleus Diseases: Coleus, when provided with a good location and the correct amount of light, water, warmth, and air circulation, are quite resistant to disease. Begin your container plantings with good quality, unused potting soil and sterile containers (sterilized with bleach water). Make sure their location is protected from cool temperatures, excessive wind, dripping from roofs or gutter, and harsh sunlight. Soggy soil and cool temperatures are a combination that invite fungal diseases such as botrytis, stem rot, and powdery mildew. Avoid overhead watering if possible and try to get the water directly to the soil. Water early in the day so the leaves are dry by evening. Coleus can also be stressed by sunscald or repeatedly being allowed to dry out, making them more susceptible to disease. Sever infestation of insect pests can also weaken a Coleus plant's ability to fend off disease.

Regularly inspect your Coleus and remove dropped leaves from the soil around the Coleus so disease organisms cannot linger there and reproduce. A few leaves dropped here and there is normal, but take note if leaf drop is sudden and excessive. Look carefully for leaves and stems that are damaged, wilted, disfigured, have black or darkened leaves or stems, black or ringed spots, or any sign of fuzzy mold or mildew (black or white). Prune and discard any leaves or stems that show symptoms and disinfect all scissors or pruning shears in bleach water or rubbing alcohol when moving from one Coleus to another. Correct any problems with the basic requirements of the plant, such as overwatering, cool temperatures, sunscald, pest infestation, or lack of air circulation. Isolate or discard a severely infected plant, especially if you have other Coleus or plants nearby. A simple anti-fungal spray can be made by using 3/4 teaspoon baking soda, 2 teaspoons vegetable oil, and a few drops of liquid soap to one quart of water in a spray bottle. Shake regularly while applying and cover all surfaces. Apply weekly if necessary. You can also experiment with making a mild tea with garlic, hot pepper, mint, or citrus peels and using that for the water base (after straining and cooling). Always test a small area of the plant with the spray for 24 hours before applying a home-made spray to the whole plant to check for possible adverse reactions, and avoid use on seedlings or cuttings without prior testing. If the problem persists, contact a local garden center for information on anti-fungal products that contain neem oil or copper and are safe for Coleus and the environment.

Cuttings: Cuttings can be taken from the non-blooming tips of coleus plants. Rooting in water is easy and they can be grown in water on a windowsill for quite some time before they begin to decline. Rooting in sterile potting soil is the best method, and rooting hormone can be helpful but is not absolutely necessary for coleus. Cuttings should be about 2-3 inches long and have at least one set of leaf nodes (with the leaves removed) beneath the surface of the soil. The soil should be kept warm and moist and rooting should occur within two weeks for most varieties. Keep in mind that it is illegal to propagate patented varieties.

For more information on growing Coleus naturally please visit our blog at http://www.rosydawngardens.blogspot.com

Coleus as Houseplants: Coleus can be grown as houseplants, but particular attention must be given to light, water, humidity, and pest control. Any Coleus can be kept in the house, so you are limited only by the amount of brightly lit space you have available. You should turn your plant regularly when grown in a window so the plant doesn't lean too much in one direction. If you don't have a window that allows bright light you might want to consider supplementing with florescent fixtures. Many people grow their Coleus under florescent grow-lights or use them as a supplement to natural light. LED grow lights are also available.

Like most houseplants, Coleus should be watered carefully. They don't want to be soggy but they don't want to be too dry either. Care must be taken not to overwater indoor Coleus, nor should they be allowed to get so dry that the plants wilt. They like a higher level of humidity than most houses have so they benefit from daily misting early in the day. You can root a coleus cutting in a vase of water on a windowsill for a temporary water garden. Ultimately you can pot up your plant and take a fresh cutting for your vase.

Since there are no natural predators in the house such as ladybugs or lacewings you will have to be diligent about checking for pests and disease regularly (see above). If you use a pesticide, make sure it is approved for indoor use. Insecticidal soap is often a good choice. Read all directions carefully.

Coleus will sometimes become lanky when grown indoors, so don't be afraid to pinch and prune your indoor Coleus to keep it tidy and prevent flowering. Another thing to keep in mind is that Coleus sometimes have different coloration in the winter months, especially when kept in a house. Usually they return to their original coloration when the days lengthen or they are moved outdoors for the summer.

For more information on growing Coleus under lights please visit our blog at http://www.rosydawngardens.blogspot.com

For more information on Coleus please visit our FAQ (Frequently Asked Questions) page and our Ordering Information page. For help in choosing which Coleus to buy please visit our Selection Guide.