Question: Some of the leaves that I have rooted aren’t producing babies. The rooted leaf seems to be healthy. In fact, it seems to be growing.
Answer: When selecting leaves to propagate, it’s best to use those that are fully mature, but not old. The usual advice is to use a leaf from a middle row, but this is misleading–this depends upon how many rows of leaves the plant has. Try to use leaves in the third or fourth row from the center. What you are looking for is a leaf that is mature, but still succulent and fresh, and not tough or woody. Very old leaves, or those with tough, woody petioles, often can be very stubborn in producing plantlets.
As for the leaf growing, this will often happen once the leaf has rooted. When growing in a covered container, as we do, these leaves will often lift the cover off. The keep this from happening, you can cut off the top portion of the leaf blade once the leaf has rooted. This will keep the leaf from growing much larger. We do this with all our leaves. In fact, we remove the entire perimeter of the leaf blade before we root them, leaving a wedge (with petiole) about the size of a dime. You can do this with even the largest of leaves. Besides saving space, this forces the rooted leaf to produce roots and babies, not a larger leaf