Monsteras are striking for their large, beautiful, deeply cut leaves. These tropical plants are popular houseplants because they are easy to care for and their foliage can add an urban jungle feel to your home. Monstera deliciosa is one of nearly 50 species in the genus which belongs to the family Araceae. Other popular monstera species include Monstera adansonii, Monstera Peru, and Monstera dubia. Although many species of monstera, will, at some point, develop the split in their leaves referred to as fenestrations, not all do. So what do you do when your monstera leaves aren’t splitting? As long as this is a growth pattern for your montera species, don’t worry—the solution is pretty straightforward.
What Is Fenestration?
Fenestration is the Latin word for “window," and in botany, it refers to natural holes or splits in the leaves of certain plants.
Why Monstera Leaves Split
The exact reason the leaves develop fenestrations is a mystery, but scientists have several theories. The most popular is that they split as they mature to allow light through to the lower leaves of the plant. Without the splits, the climbing growth habit of monsteras would cause upper leaves to shade lower leaves which could slow growth and impact the overall health of the plant.
Another theory speculates that fenestration allows rain to pass through the leaves instead of accumulating on the surface. Since plants generally don’t like having consistently wet leaves, split leaves would prevent rain from collecting on the large leaves, and allow water to reach the roots on the ground more easily.
The last major theory speculates the monstera’s fenestrations make the plant more resilient to the wind. However, since monsteras don’t tend to live in exposed areas, this theory is the least prominent of the three. Whether monstera leaves split due to one of these factors, or all of them, the general consensus is that fenestrated leaves are an adaptation that help a monstera plant thrive in its natural environment.
When Monstera Leaves Split
There are two main factors that contribute to the fenestrations developed by some species of the monstera genus: age and adequate light.
Monsteras develop fenestrated leaves as they mature, and no amount of wishing and hoping can encourage the leaves to split before the plant is ready. Young monsteras naturally have small, solid, heart-shaped leaves that increase in size as the plant grows. Usually, a healthy monstera will begin to develop the characteristic deep cuts once it has reached at least 3 feet in width and height. You will also notice that once a young monstera begins to develop fenestrations, it happens slowly and the number of splits on each leaf will increase with time. So, if you have just purchased a small monstera and are waiting for your first split-leaf, patience is key. You plant may need more time.
If you’ve had your monstera for some time and it is still not growing split leaves, it may not be receiving enough light. Monsteras need a consistent amount of bright, indirect light in order to grow split leaves as they mature. A monstera grown in low light conditions will not grow fenestrations and will push out small leaves as a way of conserving energy. If you don’t have enough natural light , consider providing your plant with a grow light.
How to Support Monstera Leaves
The best way to ensure your monstera develops strong, healthy leaves with plenty of fenestrations is to provide it with lots of bright, indirect light. Keep your plant potted in a well-draining potting mix and remember to water it regularly. Fertilized consistently during the spring and summer months to maintain a vigorous growth habit. Don’t forget to inspect your plant for signs of pests or disease on a regular basis as both can hinder the growth of an otherwise healthy monstera.
One additional trick for encouraging your monstera to grow larger and more fenestrated leaves is to provide it with a moss pole or trellis to climb. While moss poles are not necessary for growing these plants indoors, they do mimic the monstera’s natural growing environment and will result in larger, healthier foliage.
Fenestration. Merriam Webster.