Microsorum thailandicum – Blue Oil Fern

Microsorum thailandicum, commonly known as the Blue Oil Fern, is an incredible tropical fern prized for its metallic blue to blue green iridescent foliage. The narrow, leathery fronds can reflect an almost electric blue sheen depending on the lighting and viewing angle, giving the plant an appearance unlike almost any other fern.

The blue coloration is not caused by ordinary leaf pigment. Instead, it is structural coloration created by microscopic arrangements within the leaf tissue that reflect blue wavelengths of light. The effect is often strongest under lower, filtered light and can become especially noticeable on healthy, well established foliage.

Native to Thailand, Microsorum thailandicum naturally grows in warm, humid, shaded environments. It develops from a creeping rhizome and gradually forms a compact colony of upright to slightly arching fronds.

What You’ll Receive

One live Microsorum thailandicum plant. Your plant will be carefully packed to protect the foliage, rhizome, and active growing points during transit.

Plant Highlights

Metallic blue to blue green iridescent foliage

Naturally occurring structural coloration

Narrow, leathery strap shaped fronds

Compact creeping growth habit

Excellent terrarium, greenhouse, or indoor specimen

Blue coloration can become more pronounced under lower filtered light

One of the most unusual foliage ferns available

Light

Low to medium indirect light or bright filtered light is ideal.

Unlike many plants where brighter light produces stronger coloration, the blue iridescence of Microsorum thailandicum can actually appear more intense when the fern is grown under lower light conditions.

Avoid strong direct sunlight. Excessive light can wash out the blue appearance and may scorch the foliage.

Water

Keep the growing medium consistently lightly moist while still allowing good drainage.

Do not allow the plant to remain completely dry for extended periods, especially while actively producing new growth. At the same time, avoid keeping the rhizome buried in constantly saturated media.

Water thoroughly and allow excess water to drain freely.

Humidity

Moderate to high humidity is preferred.

Humidity around 60 percent or higher is ideal for maintaining healthy foliage and encouraging consistent growth. Higher humidity is especially beneficial while new fronds are developing.

Growing Media

Use an airy, moisture retentive but well draining growing medium.

A mixture containing materials such as fine orchid bark, coco chips, sphagnum moss, tree fern fiber, perlite, or pumice works well.

The creeping rhizome should remain close to the surface rather than being deeply buried.

Temperature

Warm temperatures are preferred, generally around 65 to 85°F.

Consistent warmth encourages active growth. Protect the plant from frost, cold drafts, and prolonged exposure to temperatures below its preferred tropical range.

Airflow

Provide gentle airflow, particularly when growing the plant in high humidity.

Good circulation allows the foliage and rhizome to dry appropriately while still maintaining the humid environment this fern prefers.

Fertilizer

Feed lightly during active growth with a diluted balanced fertilizer.

Microsorum thailandicum does not require heavy feeding. A diluted application every few weeks during active growth is generally sufficient.

Growth Habit

Microsorum thailandicum grows from a creeping rhizome with individual fronds emerging along the rhizome as it expands.

Mature fronds are narrow, leathery, and strap shaped. Plants gradually develop into a compact colony rather than producing the traditional feathery growth associated with many other ferns.

About the Blue Color

The metallic blue appearance is one of the defining features of this species, but the intensity can change depending on lighting, leaf age, moisture, and viewing angle.

Because the coloration is structural, the foliage may appear deep green from one angle and suddenly flash vivid blue or turquoise from another. Lower filtered light generally produces the best conditions for displaying the characteristic iridescence.

Microsorum thailandicum is an exceptional foliage plant for anyone looking for something genuinely different. Its compact growth, leathery fronds, and shifting metallic blue coloration make it an incredible specimen for humid indoor collections, terrariums, greenhouses, or shaded tropical displays.

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⚠️ Important Shipping Notes
We take great care to ensure your plant arrives safely:
• We ship every Monday and Tuesday to minimize weekend delays.
• We check destination weather on Sunday night and will add free insulation and heat packs when needed for safe delivery.
• If a plant arrives damaged, buyers must provide an unboxing video within one hour of delivery.
(We cannot be responsible for plants left outside, delayed opening, or packages exposed to heat/cold.)

🌟 Perfect For:
• Rare plant collectors
• Fans of unusual foliage
• Terrarium or greenhouse keepers
• Anyone building a unique indoor jungle