I have a Mandavilla that needs to be repotted…?
When is the best time to re-pot my Mandavilla? It is 5 ft tall and I winter it in my garage with a grow light and if needed plant heat mats.
Spring would be best to repot your plant.
Leave it in it's existing pot to overwinter.
For a mandevilla that is still quite small, work your way gradually up to that size, by moving it to a pot 2 inches larger every time its roots begin to protrude from the drainage holes of the old one. Plants grown in containers that are too big for them are much more likely to contract root rot than those in tight quarters. Make sure the pot has adequate drainage holes.