American thorow wax (Bupleurum americanum)

Also known as: American Thorowax

American thorow wax, or Bupleurum americanum, is a perennial herb known for its slender, upright stems, typically reaching heights of up to 60 cm. The plant features narrow, lance-shaped leaves that alternate along the stem, and produces small, yellow-green flowers arranged in characteristic umbels, typical of the Apiaceae family.

This plant is commonly found in open, rocky landscapes, prairies, and meadows, favoring well-drained soils. Native to North America, particularly the western United States and parts of Canada, American thorow wax thrives in sunny environments and is adaptable to various elevations, from lowlands to mountainous regions. Its deep taproots allow it to efficiently access water and nutrients, supporting its growth in diverse habitats.

In This Article

Care Tips Water Sunlight Temperature Soil Fertilize Prune Propagation Repotting Toxicity

Attributes of American thorow wax

Lifespan

Perennial

Plant Type

Herb

Plant Height

50-100 cm

Spread

15-30 cm

Leaf Color

Green

Flower Size

2-5 mm

Flower Color

Yellow-green

Images of American thorow wax

Quickly Identify American thorow wax

Identifiable by its narrow, lanceolate leaves and small, yellow-green flowers arranged in umbels. Typically found in well-drained soils.

Scientific Classification of American thorow wax

Phylum

Vascular plants

Class

Dicotyledons

Order

Apiales

Family

Umbellifers

Genus

Thorow wax

Species

American thorow wax

Planting and Growing of American thorow wax

Care Difficulty

Moderate

Watering Schedule

Every 2 days

Sunlight Requirements

Partial sun

Sunshine Duration

6-10 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

2 times a year

Repotting Season

Spring

Pot Type

Plastic, Ceramic

How to Water American thorow wax?

For Bupleurum americanum, ensure that each watering session delivers about 200 ml of water. The aim is to moisten the soil thoroughly without causing water logging. This allows the roots to absorb sufficient moisture while preventing issues like root rot. It is best to water until you see moisture seeping out of the drainage holes in the pot, indicating the soil is uniformly saturated.

What are the symptoms of an underwatered American thorow wax? ›

What should I do if my American thorow wax is not getting enough water? ›

What are the symptoms of an overwatered American thorow wax? ›

How to save an overwatered American thorow wax? ›

What Are the Sunlight Requirements for American thorow wax?

Sunlight Requirements: Partial sun

Duration of light: 4 to 6 hours

Partial sun is ideal for Bupleurum americanum, providing balanced energy for growth while avoiding heat stress. This light level enhances photosynthesis and vigor, crucial for its health.

How much sunlight does Bupleurum americanum need? ›

What are the solutions for providing ideal light? ›

What benefits does ideal lighting bring? ›

What Is the Ideal Temperature Range for American thorow wax?

Ideal Temperature: 60 ~ 75℉

Bupleurum americanum thrives best in environments where the temperature ranges from 60°F to 75°F. This range ensures optimal metabolic activity and growth rates, facilitating healthy leaf and root development.

What Soil is Best for American thorow wax?

Soil type: Loam, Sandy loam

Soil PH: 6.5 ~ 7.5

Bupleurum americanum thrives in nutrient-rich soils that provide the essential macro and micronutrients necessary for robust growth. Rich soils enhance root development, leading to healthier foliage and more abundant flowering. This plant demands soil that offers excellent drainage to prevent waterlogging. Proper drainage reduces the risk of root rot and fungal diseases, ensuring stable and continuous growth. The plant prefers soil that retains enough moisture but is not overly wet. Adequate moisture enhances nutrient uptake and supports consistent growth cycles without the stress of drought conditions.

How to Fertilize American thorow wax?

Fertilizer type: Balanced

For Bupleurum americanum, it is essential to follow a balanced approach when applying fertilizer. Use a liquid fertilizer diluted to half the recommended strength to avoid over-fertilization. For granular fertilizers, apply approximately 1 tablespoon per plant once every four months during the growing season. Keep in mind that over-fertilization can damage the plant's roots and hinder growth.

How to Prune American thorow wax?

Pruning Time: Spring, Summer, Autumn

Begin by identifying dead, damaged, or diseased stems. These should be the first to go, as removing them allows the plant to channel energy into healthier parts. Always use sharp, clean tools to prevent infections. When making cuts, ensure you're cutting back to a healthy bud or side shoot. This encourages new growth in the desired direction. It's ideal to angle the cuts slightly away from the bud to direct water away. More About Pruning Techniques→

How to Propagate American thorow wax plant?

Propagate Time: Spring, Late spring

Begin by soaking the seeds overnight to improve germination rates. Use a seed tray filled with a well-drained potting mix and lightly press the seeds into the soil. Ensure the seeds are spaced out properly to prevent overcrowding.

Select a healthy mother plant and use pruning shears to cut a 4-6 inch section of the plant. Remove the lower leaves and dip the cut end in rooting hormone before planting it in a soil-based medium.

For division, carefully dig up the plant and gently separate the roots. Each division should have a healthy section of root and shoot. Replant immediately to minimize root damage and stress.

More About Propagating Techniques→

How to Repot American thorow wax plant?

Repotting frequency: Every 1-2 years

Bupleurum americanum usually shows it's ready for repotting when roots begin to protrude from the drainage holes or it appears root-bound. Repotting during spring or summer gives the plant enough time to recover in warm weather.

Select a pot slightly larger than the current one with sufficient drainage holes. The ideal pot provides extra room for root expansion while preventing water logging, aiding in healthier growth and preventing root rot.

Go for a well-draining soil mix with a balance of organic matter and grit, like perlite or sand. Such soils prevent water retention, reduce root rot risk, and allow roots to breathe, promoting robust growth.

Toxicity

None

WARNING

The judgment on toxicity and danger is for reference only. We DO NOT GUARANTEE any accuracy of such judgment. Therefore, you SHALL NOT rely on such judgment. It is IMPORTANT TO SEEK PROFESSIONAL ADVICE in advance when necessary.