Smooth hawkweed (Hieracium laevigatum)

Also known as: Smooth Hawkweed

Canada thistle, a member of the sunflower family, is a highly adaptable perennial. It thrives in diverse habitats, including thin woodlands, fields, and even on walls. In the United States, it is classified as a noxious weed.

In This Article

Care Tips Water Sunlight Temperature Soil Fertilize Prune Propagation Repotting

Attributes of Smooth hawkweed

Lifespan

Perennial

Plant Type

Herb

Plant Height

60 cm

Spread

Not applicable

Leaf Color

Green

Flower Size

1.9 cm to 3 cm

Flower Color

Yellow

Images of Smooth hawkweed

Quickly Identify Smooth hawkweed

To identify Hieracium laevigatum, look for its smooth, hairless stems and leaves. The basal leaves are generally broader, while the upper stem leaves are narrow. The flower heads are typically bright yellow and arranged in dense clusters.

Scientific Classification of Smooth hawkweed

Phylum

Vascular plants

Class

Dicotyledons

Order

Asterales

Family

Daisy

Genus

Hawkweeds

Species

Smooth hawkweed

Planting and Growing of Smooth hawkweed

Care Difficulty

Easy

Watering Schedule

Every 2 days

Sunlight Requirements

Full sun

Sunshine Duration

4-8 hours

Ideal Temperature

60-75℉

Soil Type

Potting Mix, Peat Mix

Soil pH

6.5-7.5

Fertilizer Type

Balanced

Pruning Season

Spring, Summer

Pruning Area

Branches, Leaves

Pruning Frequency

Once a year

Repotting Season

Spring

Pot Type

Plastic, Ceramic

How to Water Smooth hawkweed?

For Hieracium laevigatum, ensure the soil is moist but not waterlogged. It's essential to water deeply, allowing the roots to fully absorb the moisture. Ideally, water until you see some drainage from the bottom of the pot but do not allow it to sit in excess water.

What are the symptoms of an underwatered Smooth hawkweed? ›

What should I do if my Smooth hawkweed is not getting enough water? ›

What are the symptoms of an overwatered Smooth hawkweed? ›

How to save an overwatered Smooth hawkweed? ›

What Are the Sunlight Requirements for Smooth hawkweed?

Sunlight Requirements: Full sun, Partial sun

Duration of light: 6 to 8 hours

Partial to full sun with at least 6 to 8 hours of sunlight daily. Sufficient light leads to healthy growth, improved flowering, and overall plant vigor.

What is the ideal lighting condition for Hieracium laevigatum? ›

How can you achieve ideal lighting conditions for Hieracium laevigatum? ›

What are the benefits of ideal lighting conditions for Hieracium laevigatum? ›

More About Sunlight Requirements Techniques→

What Is the Ideal Temperature Range for Smooth hawkweed?

Ideal Temperature: 60 ~ 75℉

For Hieracium laevigatum, an ideal growing environment is one where the temperatures are consistent between 60°F and 75°F. This range not only supports healthy photosynthesis but also ensures optimal nutrient uptake, enabling robust growth and flowering. Maintaining this temperature helps prevent stress conditions that could lead to poor health of the plant.

What Soil is Best for Smooth hawkweed?

Soil type: Sandy soil, Loam, Sandy loam

Soil PH: 6.5 ~ 7.5

Hieracium laevigatum thrives best in well-drained soils, ensuring that the roots do not become waterlogged. Proper drainage prevents root rot and supports healthy growth. The plant prefers moderately fertile soils that provide essential nutrients for its growth. This supports robust foliage and flower development, enhancing overall plant vigor. A gritty or sandy soil texture is ideal, allowing ample aeration around the root zone. This property promotes efficient nutrient uptake and root expansion.

How to Fertilize Smooth hawkweed?

Fertilizer type: Balanced

Hieracium laevigatum responds well to a moderate fertilization approach. For liquid fertilizers, use a balanced solution diluted to half-strength to avoid root burn. Typically, apply about 1-2 tablespoons of liquid fertilizer per plant each session to ensure optimal growth without overloading the soil. For slow-release granules, distribute around 2-3 ounces per square foot of soil to create a steady nutrient supply throughout the season.

How to Prune Smooth hawkweed?

Pruning Time: Spring, Summer

Start by removing any dead or damaged leaves to open up the plant for better air circulation. This also helps in preventing potential fungal disease due to trapped moisture in dense foliage. Look for stems that are leggy or overgrown and cut them back to a set of leaves or a healthy node. This promotes bushier growth and keeps the overall plant shape more compact and visually appealing. More About Pruning Techniques→

How to Propagate Smooth hawkweed plant?

Propagate Time: Spring, Early summer

Fill the seed tray with a quality seed-starting mix. Gently pat down the soil to remove air pockets. Water the soil lightly before planting, ensuring it is moist but not waterlogged.

Scatter seeds evenly across the surface of the prepared soil. Cover the seeds with a thin layer of soil or vermiculite to protect them while still allowing light to reach them if needed.

Carefully remove the plant from its pot or dig it up from the ground. Use a sharp knife or shears to divide the root ball into smaller sections, each with enough roots and shoots.

More About Propagating Techniques→

How to Repot Smooth hawkweed plant?

Repotting frequency: Every 2-3 years

Repotting is essential when the plant appears root-bound, showing roots emerging from drainage holes, or its growth appears stunted. These signs usually manifest in the early growth periods, so acting promptly enhances plant vigor.

Select a pot that is 2-3 inches larger than the current one. Ensure it has ample drainage to prevent root rot. A slightly roomy pot promotes healthy growth but avoids an excess soil mass that can retain moisture.

Use a light and well-draining soil mix, preferably one rich in organic matter. This soil type encourages proper aeration and prevents waterlogging, creating a harmonious environment for root expansion.