what do coleus seedlings look like

What Do Coleus Seedlings Look Like? A Complete Visual Guide

Coleus is one of the most popular ornamental plants grown from seed. Their brightly colored and patterned leaves add vibrant pops of color to gardens, containers and landscapes. While coleus are more commonly propagated from cuttings, growing them from seed is gaining popularity as new varieties become available. When starting coleus from seed, being able to properly identify the seedlings is crucial for success. In this complete visual guide, we will explore what coleus seedlings look like at various stages of growth so you know what to look for.

What Do Coleus Seeds Look Like?

Coleus seeds are extremely small in size, typically measuring 0.33-0.5 mm long. They have an oval or rounded shape and are brown or black in color. The seeds have a rough, wrinkled surface texture. Due to their tiny size, coleus seeds are best sown by gently pressing them into the soil surface rather than burying them. Handling them with tweezers or a moistened toothpick makes planting easier.

Germination: Identifying Newly Sprouted Coleus Seedlings

Given the right conditions, coleus seeds will germinate in 7-15 days Here’s how to identify newly sprouted coleus seedling

• Look for two small round green leaves emerging from the soil. These first two leaves are called cotyledons. They sustain the plant until true leaves emerge.

• Coleus cotyledons often start off pale or lime green in color, not yet showing the vibrant colors of mature foliage.

• The cotyledons are quite small and delicate, just 1-5 mm across. Handle new sprouts with care.

• Check pots daily for new seedlings poking through the soil. Gently brush away soil if needed to uncover them.

Spotting the tiny cotyledons means your coleus seeds have successfully germinated. Though plain at first, these embryonic leaves sustain the seedling until it can produce its own food through photosynthesis.

Early Seedling Stage: First True Leaves Emerge

In the days and weeks following germination, the first true leaves will begin growing between the cotyledons:

• These new leaves reveal the characteristic foliage shape, scalloping, colors and patterns of the coleus variety.

• However, the leaves may still be mostly lime green at first, developing richer colors later on.

• Leaves remain small and roundish, typically 5-15 mm wide. Look closely for signs of mature traits.

• Check for serrated, lobed or ruffled leaf margins and veining patterns.

The first true leaves display the seedling’s genetic potential more than the cotyledons do. Observing them helps identify varieties as the seedlings grow.

Later Seedling Stage: Maturing Foliage Traits Emerge

After several sets of true leaves emerge, the coleus seedlings take on more mature foliage traits:

• Leaf shape, scalloping, colors and veining become clearly recognizable for the variety.

• Leaves get larger and their mature palette of colors develops.

• Overall plant form fills out as stems lengthen and leaf size increases.

• Flower buds may form, signaling transition to adulthood. Pinch off buds to prolong foliage growth.

At this stage, it becomes easier to match seedlings to the expected foliage traits of the coleus variety you planted.

Signs of Healthy, Vigorous Coleus Seedlings

When assessing your coleus seedlings, look for these signs of robust health and vigor:

• Large, evenly shaped leaves with rich colors and distinct patterns. Avoid spindly plants.

• Sturdy stems that can support the leaves without drooping or flopping over.

• Upright, upright growth habit – not limp or stretching toward light.

• Intense leaf colors that match the variety’s description.

• Steady growth rate once established.

• Mature true leaves that resemble the adult coleus in shape and traits.

Prioritize stocky, brightly colored seedlings whose leaves most closely match the target variety. Cull out any weak, stunted or atypical specimens.

Ideal Conditions for Coleus Seedling Success

To grow robust coleus seedlings, provide:

• Warm temperatures of 70-80°F for germination and growth.

• Consistent moisture – never let soil dry out completely.

• Good drainage and air circulation.

• High humidity, especially for sprouting seeds.

• Bright indirect sunlight once seedlings are established.

• Fertilizer to fuel growth after true leaves emerge.

• Prompt thinning and transplanting to avoid crowding.

Meeting young coleus seedlings’ needs ensures they grow into vibrant, healthy adult plants. Pay close attention in those first weeks and months to set your seedlings up for success. With diligent care and observation, coleus grown from seed can flourish just as well as those propagated from cuttings.