A young plant may simply be healthy and immature
Small, heart-shaped leaves are normal on young Monstera deliciosa. There is no dependable birthday, height or exact leaf count at which your plant must produce holes. A date on a care chart cannot account for its growing conditions or propagation history.
If leaves are firm and growth is steady, you do not need to treat the lack of holes as a disease. New shoots after pruning or establishment of a cutting may also look less mature.
Look at the whole growth pattern
A plant in a dim corner producing smaller leaves and stretched stems may benefit from brighter, filtered light. Move it gradually and check for harsh sun on the foliage. Window direction alone is not enough: nearby buildings, curtains and distance from the glass change the light reaching a leaf.
Make climbing possible
Monstera is a climbing plant. Offer a stable trellis or pole as it becomes larger. Secure the main stem loosely and leave the leaf stalks free to move. Support helps manage its growth; it is not a guarantee that the next leaf will have holes.
Check roots and routine care
Persistent wetness, repeated severe drying or other stress can limit growth. Follow the watering checks and investigate yellowing or wilting before focusing on leaf shape.
If the plant is actively growing and needs feeding, follow the houseplant fertiliser label. Do not increase fertiliser just to force splits. Roots and light must support growth first.
Keep a simple leaf record
Photograph each new leaf once it has opened and firmed up. Note its size, shape and the date. Compare several new leaves rather than setting a two-week deadline; growth can slow substantially in a dim season.
If new leaves remain solid but otherwise healthy, continue steady care. If they become progressively smaller, yellow or distorted, investigate those symptoms. Healthy growth is the useful goal; holes alone are not a health score.