Kurogane holly (Ilex rotunda)

Also known as: Small-fruited holly

The Kurogane holly (Ilex rotunda) is a striking evergreen holly native to Japan that can reach heights of up to 15 meters. This species has been cultivated in the United States for around 200 years. It produces bright red berries that ripen from fall through winter, providing a beautiful visual display during the colder months.

In This Article

Care Tips Water Sunlight Temperature Soil Fertilize Prune Propagation Repotting Toxicity

Attributes of Kurogane holly

Lifespan

Perennial

Plant Type

Tree

Plant Height

15 m

Spread

11 m to 14 m

Leaf Color

Green Blue

Flower Size

5 mm

Flower Color

White Purple

Images of Kurogane holly

Quickly Identify Kurogane holly

Identify Ilex rotunda by its smooth, grayish-brown bark, oblong glossy green leaves with small serrations, and bright red berries which appear in winter.

Scientific Classification of Kurogane holly

Phylum

Vascular plants

Class

Dicotyledons

Order

Aquifoliales

Family

Holly

Genus

Ilex

Species

Kurogane holly

Planting and Growing of Kurogane holly

Care Difficulty

Easy

Watering Schedule

Every 2 days

Sunlight Requirements

Partial 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

2 times a year

Repotting Season

Spring

Pot Type

Plastic, Ceramic

How to Water Kurogane holly?

Watering Ilex rotunda involves soaking the soil thoroughly but avoiding waterlogging. The goal is to provide enough moisture so that the water reaches the plant's roots but ensures there is adequate drainage. Water deeply and then allow the soil to dry slightly on the surface before watering again.

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What Are the Sunlight Requirements for Kurogane holly?

Sunlight Requirements: Partial sun

Duration of light: 4-6 hours

Partial sun exposure of 4-6 hours daily is ideal, ensuring photosynthesis while preventing stress. This balance helps maintain optimal health and vigor in Ilex rotunda.

Best Light Exposure for Growth ›

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What Is the Ideal Temperature Range for Kurogane holly?

Ideal Temperature: 60 ~ 75℉

Maintaining the ideal temperature range of 60°F to 75°F is crucial for Ilex rotunda as it promotes optimal growth and prevents stress. This temperature range helps in maximizing photosynthesis and ensuring proper nutrient uptake, leading to a healthier plant with robust foliage.

What Soil is Best for Kurogane holly?

Soil type: Loam, Sandy loam, Clay soil

Soil PH: 6.5 ~ 7.5

Ilex rotunda requires soil with good moisture retention capabilities. Loamy or sandy loam soil types are particularly suitable due to their ability to hold sufficient moisture while allowing excess water to drain away, preventing root rot. The plant thrives in nutrient-rich soils. Including organic matter like compost improves soil fertility, providing a robust source of nutrients necessary for healthy growth and vibrant foliage. This species needs well-drained soil to avoid waterlogged conditions. Good drainage ensures that the roots get enough air and prevents fungal diseases, encouraging a healthy root system.

How to Fertilize Kurogane holly?

Fertilizer type: Balanced

For Ilex rotunda, it is crucial to avoid over-fertilization. Use a balanced fertilizer, such as a 10-10-10 formula, applying approximately 1 tablespoon per square foot. Ensure the fertilizer is evenly distributed around the plant base, and always follow up with thorough watering to assist in nutrient absorption.

How to Prune Kurogane holly?

Pruning Time: Spring, Summer

Avoid pruning Ilex rotunda during late autumn as new growth may not survive the winter cold. Instead, aim for early spring when regrowth is most vigorous and the plant can recover quickly. Remove no more than one-third of the plant at a time to prevent shock. Over-pruning can stunt growth and lead to a less aesthetically pleasing appearance. More About Pruning Techniques→

How to Propagate Kurogane holly plant?

Propagate Time: Spring,Early summer

To propagate Ilex rotunda from seeds, collect seeds from mature berries. Ensure that the seeds are fully ripened, typically indicated by a change in berry color.

Select healthy, disease-free stems for cuttings. Cut a 4-6 inch segment, making sure there are several nodes along the stem. Remove lower leaves to reduce transpiration.

Sow seeds in a well-draining soil mix, lightly covering them with soil. Maintain a consistently moist environment, using a propagation dome or clear plastic to retain humidity.

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How to Repot Kurogane holly plant?

Repotting frequency: Every 2 to 3 years

The Ilex rotunda requires repotting when its roots begin to outgrow the current container or start circling inside. Other signals include slowed growth or the evaporation of potting soil. Early signs dictate it's time to relocate the plant to a new space to maintain health and vitality.

Select a pot that is 2-3 inches larger in diameter than the current one. This not only gives ample room for root expansion but also prevents waterlogging. A pot with proper drainage holes is essential to avoid root rot and to promote healthy plant growth, ensuring the plant has the best foundation to thrive as it transitions.

For Ilex rotunda, the ideal soil is a well-drained potting mix, rich in organic matter. Such soil promotes root oxygenation and retains necessary nutrients for plant development. It enhances drainage, which is crucial for preventing root rot, and provides a balanced environment for nutrient uptake.

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Toxicity of Kurogane holly

Is Kurogane holly toxic to humans?

Kurogane holly is known to have a moderate toxic effect on humans, which can result in poisoning if ingested. Every part of the plant is deemed toxic, and consuming it may lead to various symptoms. Those who eat any parts of kurogane holly might suffer from gastrointestinal issues, including nausea, vomiting, and abdominal discomfort. Furthermore, symptoms can progress to neurological reactions such as dizziness and confusion. Given that the entire plant is poisonous, it is important to exercise caution to avoid unintentional ingestion, especially in areas where kurogane holly is found.

Is Kurogane holly toxic to cat?

Kurogane holly is known to carry a moderate degree of toxicity for cats, presenting a potential health hazard if any part of the plant is ingested. If a cat inadvertently consumes kurogane holly, which is entirely toxic, it may display symptoms of physical distress or illness. Should ingestion occur and result in poisoning, it is crucial for cat owners to promptly seek veterinary assistance to safeguard the health and safety of their beloved feline friends.

Is Kurogane holly toxic to dog?

Kurogane holly presents a moderate toxicity hazard for dogs. Canines might accidentally ingest various parts of this plant, which can lead to potential poisoning scenarios. The entirety of the plant is toxic, and consumption may trigger a range of concerning symptoms. Dog owners should remain alert for indicators such as gastrointestinal distress, vomiting, diarrhea, or even more severe reactions based on the quantity consumed. If a dog shows any atypical behaviors or health issues after exposure to kurogane holly, it is crucial to obtain prompt veterinary assistance to secure the best possible outcome for the animal.

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.

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