Coleus is a beautiful plant that can add a pop of color to any garden or indoor space. Because its leaves are different shades of pink, lime green, and burgundy, it’s easy to see why so many gardeners love it. Coleus is easy to grow from seeds and can get up to 3 feet tall. It is a mint family plant. Growing coleus from seeds is a great way to get started, whether you want to add some texture to your flower beds or make your home look better.
Coleus are gorgeous ornamental plants treasured for their vividly colored and patterned foliage. They come in a stunning range of leaf shapes, textures and hues. Coleus bring drama to gardens, containers and landscaping with their dynamic colors and forms.
These plants are typically started from cuttings to preserve their unique traits But growing coleus from seeds is gaining popularity as more distinctive new varieties become available When starting coleus from seed, it’s important to properly identify the seedlings as they germinate and grow.
In this article, I’ll give coleus lovers a guide to recognizing coleus seedlings and caring for them Correctly identifying seedlings ensures you select the best ones to grow on to maturity. Let’s explore what pre-grown coleus starts should look like at various growth stages
What Do Coleus Seeds and Seedlings Need?
Before we look at what to expect as seeds sprout, let’s review optimal conditions for germination:
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Coleus seeds require warmth, and germinate best at 70-75 °F. Use a heat mat or warm spot.
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Seeds need consistently moist soil. Cover pots with plastic wrap to retain humidity.
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Good drainage and aeration is vital. Use loose seed starting mix.
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Light is not necessary at first. Move to bright indirect light after sprouting.
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Seeds will germinate in 7-30 days if given proper conditions. Be patient!
Giving seeds and seedlings an ideal environment encourages healthy, vigorous growth right from the start.
What Do Coleus Seedlings Look Like at Sprouting?
Coleus seeds will typically germinate in 7-15 days after sowing if conditions are right. Here’s what to look for once they sprout:
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The first seedling growth is a set of round embryonic leaves called cotyledons. Look for two green, roundish leaves emerging from the soil.
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Cotyledons may be pale or lime green. Later true leaves will show the variety’s expected colors.
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The first shoots are very fragile and tiny. Handle seedlings carefully to avoid damage.
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After the cotyledons open, the first true leaves will start growing between them.
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Check pots daily for new sprouts. Gently brush away soil to uncover emerging seedlings if needed.
Coleus cotyledons are quite small and delicate at first. But recognizing them means you know seeds successfully germinated.
How Do Coleus Seedlings Look After Cotyledons Emerge?
In the weeks after the cotyledons open up, the baby coleus will start to show its mature foliage characteristics:
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The next leaves to emerge are the true leaves. These will reveal the coleus variety’s leaf shape, scalloping, colors and patterns.
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True leaves may start lime green and develop rich colors later. Observe the leaves’ margins and veining.
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Growth is slow at first. Leaves will be small and relatively round. Focus on pattern and color potential.
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When secondary leaves grow after the first true leaves, the overall plant form becomes clearer.
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Select the seedlings with best coloration and leaf shapes matching the variety’s description.
It takes several sets of true leaves to assess seedlings’ accurate colors and forms. Be patient, and choose the best performers to pot up.
Signs of Healthy, Robust Coleus Seedlings
When evaluating your coleus seedlings, look for these signs of vigor:
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Leaves are large, evenly shaped, and unblemished by disease or pests. Avoid spindly plants.
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Stems are stout enough to hold up leaves, not thin and floppy.
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Seedling stands upright, not drooping limply. Select stocky over leggy specimens.
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Leaf colors match variety descriptions. Intense colors indicate health.
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Growth rate is steady, though slower than cuttings.
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True leaves resemble mature coleus foliage in shape and pattern.
Prioritize stocky, brightly colored seedlings with leaves that match the coleus variety you planted. Cull any weak, stunted or off-type seedlings.
When to Transplant Coleus Seedlings
Coleus seeds started indoors can be transplanted outside after:
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They have grown 4-6 true leaves after the cotyledons.
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All danger of frost has passed. Coleus cannot tolerate any cold.
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Seedlings are showing accurate leaf colors, shapes and patterns.
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Plants are stocky and strong, not leggy or wilted.
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Outdoor soil temperature has warmed to at least 65 °F.
Wait to transplant until seedlings are vigorous and displaying mature coleus traits. Handling before plants are sturdy risks damage or shock.
How to Care for Coleus Seedlings
Coleus seeds and seedlings thrive with:
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Warm temperatures between 70-80°F during the day.
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High humidity. Cover pots or trays with plastic wrap or domes.
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Moist soil. Avoid both soggy mix and drought.
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Gentle air circulation prevents fungal problems.
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Dilute fertilizer when true leaves emerge. Don’t overfeed.
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Bright indirect light once established. Direct sun burns tender leaves.
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Transplant into cell packs or small containers when rooted.
Proper care produces the healthiest, most colorful coleus seedlings. With good germination and growing conditions, seeded coleus can rival striking cuttings.
Achieving Maximum Diversity from Seeded Coleus
One advantage of growing coleus from seed is the genetic diversity you can achieve. Here are some tips:
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Research and select seeds from coleus species rather than named cultivars. These capture a wide gene pool.
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Grow as many different coleus varieties and species as you can. Compare their traits.
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Save seeds from your healthiest, most vivid plants to sow next year.
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Trade seeds with other growers to gain access to more diversity.
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Cross-pollinate your best plants to create exciting new variations.
Patient gardeners who harvest and re-sow seeds can develop uniquely patterned coleus suited exactly for their growing conditions. A varied seed stash ensures exciting surprises!
Be Patient – Coleus Seedlings Need Time
It’s tempting to toss out delicate, plain-looking coleus seedlings in favor of quick colorful cuttings. But be patient and let them grow. Slow-growing seedlings often transform into stunning mature plants. Taking time to properly identify coleus seedlings prevents discarding hidden gems.
With the right environment, time and selection, seeded coleus can rival fancier named varieties. Just be sure to give them several sets of true leaves before assessing seedlings’ merits and choosing which to pot up. Patient gardeners are rewarded with vigorous, diverse coleus adapted to their unique gardens.
Tips for fail-proof coleus seed germination
Growing coleus from seed is easy to do. These seeds are tiny and need light and warmth to germinate.
- Coleus seeds should be planted indoors 8 to 12 weeks before the last spring frost.
- Coleus seeds are very tiny. Lightly sprinkle them so that they don’t grow too close to each other. One at a time, you can pick them up with a wet toothpick.
- Coleus seeds need light to sprout. Gently press the seeds into the soil or growing medium, but don’t add more soil on top of them.
- The seeds will start to sprout in 10 to 14 days if you keep them moist. A humidity dome helps the seeds stay moist until they sprout.
- If you need to, use a heating pad to keep the soil between 70 and 75ºF.
- After the seeds have sprouted, water the soil from the bottom up to keep it moist.
- Use grow lights or put seedlings in a sunny window.
- Thin out your coleus seedlings once they have sprouted. They will grow faster if the roots have less competition.
- You can start getting the seedlings ready to move outside when they have at least two sets of true leaves.
- Before planting outside, wait until there is no longer any risk of frost and the temperature stays above 60ºF.
This Coleus starter kit comes with everything you need to start growing coleus from seed.
How to grow coleus plants outdoors
Coleus comes in many colors and color combinations and looks beautiful in both containers and flower gardens. Coleus grown from seed prefers dappled sun to half shade. Too much sun will fade the bright colors and bleach the leaves. Coleus will wilt in the hot afternoon sun, so be sure to keep it well watered. As long as the soil stays moist, the leaves will spring back when the sun goes down.
Well-draining soil is important for coleus so that the roots don’t rot.
Growing coleus in containers will mean more frequent watering than coleus grown in a ground bed. Coleus grown in pots needs water every day, or sometimes twice a day, depending on how fast it dries out or gets hot. Make sure the pot has good drainage.
When growing coleus in the ground, water whenever the top 1 or 2 inches is dry. Coleus leaves will dry out and turn brown when it is not getting enough water.
Fertilizer is not necessary when growing coleus in fertile garden soil. But a balanced fertilizer applied once a month can produce bigger plants.
Container-grown coleus will need more frequent fertilizing as frequent watering can deplete the soil of nutrients.
Always use a balanced fertilizer for coleus. One with more phosphorus will result in a leggy plant.
coleus seedlings update, what do coleus seedlings look like
What do Coleus flowers look like?
In the late summer coleus plants will grow flower stalks with rows of small blue or white flowers. The blossoms are insignificant, but bees and other pollinators love them. If you don’t like how they look you can cut them off, which will help encourage the plant to redirect energy toward producing more foliage.
How to plant Coleus seeds?
The soil should be well-draining and enriched with organic matter. This can be achieved by mixing compost or aged manure into the soil. Ensure that the soil is loose and free from any debris or weeds. A pH level between 6.0 and 7.5 is ideal for coleus plants. Once the soil is prepared, it’s time to plant the coleus seeds.
How big does a Coleus grow?
New colors and patterns are introduced regularly including dwarf varieties, trailing types and big-leaf, upright plants that grow to 3 1/2 feet tall. At maturity, coleus produces tiny blue or white flowers on spikes but these are often pinched out to encourage more brilliantly colored leaves.
Is Coleus a shade plant?
But there is coleus for everyone. From sun varieties to ones that perform best in shade. There are upright ones and low-lying trailing ones. Some coleus have large leaves, some have small leaves, and some have ruffled or elongated leaves. They come in almost all colors, except blue.
