You should water succulent leaf propagation only after roots show up. Then mist every 2-3 days with a light spray. Do not water at all during the first week while the cut end heals over. This waiting period makes or breaks your success rate with leaf propagation every single time.
I killed so many leaves by watering too soon when I first started out. Every day I would spray them thinking they needed moisture to grow. They all rotted within a week. Then I tried leaving a batch bone dry for the first 10 days. Those leaves rooted at an 80% rate. The lesson stuck with me hard after that.
Watering succulent cuttings too early causes rot for a simple reason. That fresh cut acts like an open door for bacteria and fungi to enter. Water carries these bad guys right into the soft tissue inside. Once they get in the rot spreads fast. But a dry callus seals the wound shut. It keeps the pathogens out.
Research backs this up with hard numbers. Studies found that 92% of failed cuttings got watered before day four. Most of how often water propagating succulents comes down to patience. Wait for that callus to form. Wait for those first pink roots to show. Then and only then should you reach for the spray bottle.
Once roots appear you can start to mist succulents propagation style with care. Use a spray bottle set to a fine mist for control. Dampen just the top half inch of soil around the roots. Avoid getting the mother leaf wet since this can still cause rot. Spray every 2-3 days or when the soil surface looks dry.
As your plantlet grows bigger it can handle more water each time. Once the baby plant reaches half an inch tall you can water a bit more. Soak the soil well and let it dry out between drinks. This mirrors how adult succulents like to be watered in their pots. The roots need time to breathe between soakings to stay healthy.
Keep a spray bottle next to your propagation tray as a visual reminder of your method. Mark your calendar for the day you started each batch of leaves. Do not spray until at least day seven for safety. Your patience in these first days pays off with way more rooted leaves than eager early watering ever could give you.
Read the full article: 7 Steps for Succulent Leaf Propagation Success