Monstera obliqua ‚Yasuni‘ - Care

The Yasuni likes it bright, but its paper-thin, parchment-like leaves are sensitive to too much light. A bright spot with filtered light near a window is ideal. Here's an honest note: Specialized breeders report that the Yasuni form can tolerate some gentle morning sun and even uses it for fenestration development – however, most other sources on Obliqua generally advise against any direct sun. Since sources disagree on this and the leaves are so sensitive, we would rather err on the side of caution and avoid direct sun altogether rather than experimenting. Too little light will also slow down the characteristic, extreme fenestration, which develops over years on mature plants anyway.

Water when the top layer of substrate (roughly the top 1-2 inches) has dried out. The soil should be evenly moist afterward, but never waterlogged. The Yasuni is sensitive to both extremes, too dry and too wet, and quickly tends to rot if the soil remains constantly wet. A slightly smaller pot is advantageous here: In pots that are too large, the top layer dries out while the lower parts remain wet, which can easily lead to overwatering. It's best to water with lukewarm, low-lime water; filtered water or rainwater is ideal.

The Yasuni grows extremely slowly, so the fertilization is correspondingly restrained. During the growth phase, one application every 4 to 6 weeks with a diluted, balanced liquid fertilizer is usually sufficient; half strength is a good rule of thumb here. Exactly how much depends on the specific product and its concentration – it's best to follow the dosage instructions on the packaging rather than a blanket rule. Since growth is slow anyway, fertilizing too often or too strongly here can cause damage more quickly. In the winter months, it is sufficient to significantly reduce fertilization rather than stop it completely.

We consciously alternate between different fertilizers for our own plants – currently including COMPO COMPLETE, Foliage Focus, Liquid Gold Leaf, and Hesi TNT-Complex, supplemented with Hesi Root Complex, Hesi PowerZyme, and CalMag as needed.

It should be loose, coarse-grained, and quickly draining – the coarse component (orchid bark, perlite, a bit of sphagnum moss) can be high, as it is particularly sensitive to compacted or persistently wet soil. When repotting, choose a pot only slightly larger than the previous one – the Yasuni dislikes excess soil volume around its roots.

This is where the Yasuni is most demanding: Normal indoor air (approx. 40 %) isn’t sufficient in the long run; the leaf margins will quickly turn brown and become brittle. You should aim for at least 70 %, preferably 80 % or higher—a level that’s difficult to maintain long-term in a typical living room. That’s why most experienced growers cultivate it in a terrarium, display case, or plant cabinet with good air circulation. Misting provides only a negligible and short-lived benefit, but it wets the leaves, which is an unnecessary risk for this rot-prone plant—a humidifier or a closed display case is more reliable. It is also sensitive to temperature: 20 to 28 °C during the day is ideal, and at night the temperature should not drop below 18 °C. It cannot tolerate drafts or temperature fluctuations at all.

Patience is the most important tool when caring for this plant: Under ideal conditions, a new leaf per month is realistic; under normal living room conditions, however, growth is often significantly slower—sometimes even coming to a standstill for several months, especially in winter. This is completely normal and not a result of improper care. In young plants, the characteristic extreme lacy pattern is usually almost completely absent; at first, the leaves appear to have fairly normal perforations—this is not a sign that you have the wrong plant, but rather a trait that develops over the years as the plant matures. With a climbing support (moss stick or coconut fiber stick), it grows more vigorously and, over the years, develops the extreme lacy pattern typical of Obliqua, in which up to 90 % of the leaf surface can consist of holes—without support, it remains more compact and bushy. Occasionally, it forms leafless runners (stolons) that can develop new roots in a moist, dark spot—this, too, is normal growth behavior.