Tuberous stoneseed (Lithospermum tuberosum)

Also known as: Purple Gromwell, Bearded Lithospermum

The name "tuberous stoneseed" derives from the plant's hard, stone-like seeds. Belonging to the forget-me-not family, this plant features yellow blooms in the spring and has hairy leaves. It is indigenous to the United States.

In This Article

Care Tips Water Sunlight Temperature Soil Fertilize Prune Propagation Repotting Toxicity

Attributes of Tuberous stoneseed

Lifespan

Perennial

Plant Type

Herb

Plant Height

30 cm to 61 cm

Spread

Approximately 20 cm

Leaf Color

Green

Flower Size

Around 1.5 cm

Flower Color

Yellow

Images of Tuberous stoneseed

Quickly Identify Tuberous stoneseed

Look for detailed lanceolate leaves with a hairy texture, and striking purple flowers that bloom in clusters. The plant has tuberous roots which are used for identification.

Scientific Classification of Tuberous stoneseed

Phylum

Vascular plants

Class

Dicotyledons

Order

Boraginales

Family

Borage

Genus

Gromwells

Species

Tuberous stoneseed

Planting and Growing of Tuberous stoneseed

Care Difficulty

Easy

Watering Schedule

Every 2 days

Sunlight Requirements

Partial sun

Sunshine Duration

6-10 hours

Ideal Temperature

60-70℉

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, Terracotta

How to Water Tuberous stoneseed?

When watering Lithospermum tuberosum, aim to keep the soil consistently moist but not waterlogged. Use approximately 500 milliliters per watering session to thoroughly hydrate the root zone without causing standing water.

What are the symptoms of an underwatered Tuberous stoneseed? ›

What should I do if my Tuberous stoneseed is not getting enough water? ›

What are the symptoms of an overwatered Tuberous stoneseed? ›

How to save an overwatered Tuberous stoneseed? ›

What Are the Sunlight Requirements for Tuberous stoneseed?

Sunlight Requirements: Partial sun

Duration of light: 4-6 hours of sunlight

Partial sun is the ideal light range for Lithospermum tuberosum, providing it with 4-6 hours of filtered sunlight daily. This setup allows for optimal growth, healthy foliage, and vibrant blooms while preventing damage due to excessive exposure.

What is the recommended light for Lithospermum tuberosum? ›

How can I achieve the ideal lighting conditions? ›

What are the benefits of ideal lighting for Lithospermum tuberosum? ›

What Is the Ideal Temperature Range for Tuberous stoneseed?

Ideal Temperature: 60 ~ 70℉

Lithospermum tuberosum thrives best in an environment where temperatures are kept between 60 and 70 degrees Fahrenheit. This range provides optimal conditions for photosynthesis, ensuring the plant can efficiently convert sunlight into energy. Maintaining these temperatures supports healthy growth, vibrant foliage, and strong resistance to diseases common in less ideal conditions.

What Soil is Best for Tuberous stoneseed?

Soil type: Sandy loam, Loam

Soil PH: 6.5 ~ 7.5

Lithospermum tuberosum thrives in well-draining soil that prevents waterlogging. This helps the plant maintain healthy roots and reduces the risk of root rot, encouraging robust growth. This plant prefers soils that retain moderate moisture levels to support its water needs without creating soggy conditions. Such balanced moisture helps ensure the plant can absorb nutrients effectively. Lithospermum tuberosum benefits from nutrient-rich soils that boost its growth by providing essential minerals and organic matter. This nutrient availability enhances flowering and overall vitality.

How to Fertilize Tuberous stoneseed?

Fertilizer type: Balanced

For Lithospermum tuberosum, the general rule of thumb is to apply a balanced liquid fertilizer at a concentration of 1 teaspoon per gallon of water. When preparing to apply a solid slow-release fertilizer, use approximately 1 tablespoon per square foot of soil area to ensure even distribution and avoid fertilizer burn.

How to Prune Tuberous stoneseed?

Pruning Time: Spring, Summer, Autumn

Begin by sterilizing your pruning tools to avoid infections. Start pruning by removing dead and damaged branches, which will keep the plant healthy and promote new growth. Proceed to thin out the plant by cutting any overcrowded branches to improve air circulation and sunlight penetration. Trim the top sections to maintain the desired height and shape gently. After pruning, water the plant to help it recover from the stress. More About Pruning Techniques→

How to Propagate Tuberous stoneseed plant?

Propagate Time: Early spring, Late spring, Early summer

Collect mature seeds from viable plants in early spring. Soak seeds in warm water for 24 hours to enhance germination. This process helps to break seed dormancy and improve the likelihood of successful sprouting.

In late spring, use pruning shears to cut 4-6 inch lengths of healthy stems. Remove the lower leaves, keeping just a few at the top. Dip the cut end in rooting hormone to encourage root development before planting in pots.

During early summer, dig up the mature plant and gently divide the root clumps using sterilized tools. Each division should have a healthy root system and at least one growing shoot. Replant divisions promptly to reduce stress.

How to Repot Tuberous stoneseed plant?

Repotting frequency: Every 2-3 years

Lithospermum tuberosum shows signs of needing repotting when it outgrows its current container, with roots visibly emerging from drainage holes or the soil surface becomes compacted. Choose to repot in spring or early summer as the plant actively grows. This timing ensures it can swiftly establish itself in the new potting mix.

Select a pot that is just slightly larger than the current one, with ample drainage holes at the bottom. A slightly larger pot avoids excessive soil retaining moisture, which could lead to root rot. Clay or terracotta pot materials can be advantageous for Lithospermum tuberosum as they allow better air circulation and prevent waterlogging.

Opt for a well-draining sandy mix that mimics the plant's natural habitat. Such a mix allows excess water to drain, preventing root rot and ensuring the roots receive enough oxygen. Incorporating components like perlite or coarse sand improves drainage further, fostering healthier growth.

Toxicity

Ingestion

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.