Why Are My Monstera Leaves Not Splitting?

Solid, heart-shaped monstera leaves are disappointing when you bought the plant for the splits. The good news is that the causes are few and all of them are fixable — or resolve on their own with time.

What fenestration actually is

The holes and splits are called fenestrations, from the Latin for window. The leading explanation is that they let light through to leaves lower down the plant, and let strong winds and heavy rain pass through a large leaf without tearing it.

Two things matter for our purposes:

1. Each leaf’s pattern is set before it unfurls. A solid leaf will never develop holes later.
2. Fenestration is a mature growth trait. The plant has to be ready.

That means you judge any fix by the new leaves, not the old ones.

Cause 1: not enough light

The most common reason by a distance. Producing large fenestrated leaves is energetically expensive, and a plant in dim light simply cannot afford it.

How to tell: the plant is more than about 8 ft from a window, or in a spot where you would need a lamp to read comfortably at midday. New leaves are the same size as, or smaller than, the old ones.

The fix: move it to within 3–6 ft of an east or south-facing window. If the sun is directly on the leaves at midday, filter it with a sheer curtain — direct sun through glass scorches monstera leaves.

Expect a few new leaves before you see a change; the plant needs to build reserves first.

Cause 2: it is still young

Monsteras go through a juvenile phase producing solid, heart-shaped leaves that look nothing like the plant you imagined buying. This is completely normal and lasts one to three years.

How to tell: small plant, bought within the last year or two, leaves under about 8 inches across.

The fix: patience, plus good light — which speeds the transition substantially. The first splits usually appear as shallow notches at the leaf edge, developing into full splits on later leaves, and interior holes later still.

Cause 3: nothing to climb

This is the one most people miss. Monsteras are hemiepiphytes — they germinate on the forest floor, find a tree, and climb it, producing progressively larger and more fenestrated leaves as they ascend.

A monstera sprawling sideways out of a pot on a shelf is, as far as the plant is concerned, still on the forest floor.

How to tell: the plant grows outward rather than upward, and its aerial roots hang loose with nothing to grip.

The fix: give it a moss pole, coir pole or wooden plank.

1. Insert the pole at the back of the pot, pushing it firmly to the base.
2. Tie the main stem to it loosely with soft plant ties — snug enough to hold, loose enough not to constrict.
3. Keep a moss pole lightly damp so aerial roots grip and grow into it.
4. Continue tying as it grows upward.

Aerial roots attach within a few weeks, and the difference in leaf size within one season is usually obvious.

Cause 4: root-bound or underfed

A plant that has run out of root space and nutrients cannot support large leaves.

How to tell: same pot for three or more years, roots circling out of the drainage holes, and new leaves noticeably smaller than older ones.

The fix: repot one size up in spring into a chunky aroid mix — roughly 40% potting soil, 30% orchid bark, 20% perlite, 10% coco coir. Feed monthly at half strength from March through September.

Cause 5: it is not a Monstera deliciosa

Worth ruling out, because plant labelling is inconsistent.

• Rhaphidophora tetrasperma, sold as “mini monstera” or “monstera minima”, is a different genus. It does fenestrate, but the leaves stay much smaller.
• Monstera adansonii produces oval leaves with interior holes but no marginal splits — that is its normal appearance, not a problem.
• Philodendron hederaceum, frequently confused with a young monstera, has heart-shaped leaves and never fenestrates at any age.

If your plant has thin, soft, perfectly heart-shaped leaves and trails rather than climbs, check whether you actually have a heartleaf philodendron.

Realistic expectations

With good light, a moss pole and regular feeding, a healthy young monstera typically starts splitting within a season or two. Interior holes come later still, on a plant that has been fenestrating reliably for a while.

The full care routine is in the Monstera deliciosa care guide.