Will my plumeria drop leaves in the winter and be dormant? Should I keep it in the sun or shade? How much should I water it?
Plumeria (also called frangipani) is a member of the Apocynaceae (dogbane) family, and is a native of the tropics. In that habitat, it is a small tree that grows to about 30 feet in height.
If your house temperature stays at 65-70 degrees F (18-21 degrees C) and it gets plenty of light, the plumeria may not go dormant. If this is the case, and it’s in a sunny area, let it keep its leaves, water sparingly and monitor for pests like spider mites. And if you definitely don’t want the plant to go dormant, place it under grow lights (for about 16 hours a day).
However, if it starts to go dormant (the more likely case, as indoor conditions are usually not ideal) –i.e., by dropping its leaves and exhibiting no new growth – it will no longer need water (which could encourage root rot) or light. Place it in a cool spot – e.g., your basement – where the temperature is no lower than 40 degrees F (4 degrees C) – make sure to keep it from freezing. The plant will look like a stick. Some experts recommend watering the plant a little, keeping it barely moist, e.g., if the stem looks particularly dry. Others stop watering it totally.
You can bring the plant in in its pot, or remove it from the pot, shake off the soil and wrap its roots in newspaper, before hanging them or standing it in pot. The bare roots should not be touch the (cold) ground.
Once temperatures are warmer, the plumeria will begin to sprout, so you can start watering and fertilizing lightly. Bring it upstairs so it get some sun. Move it outside (repot it if needed) only once all danger of frost has passed. Once the warm weather arrives, new leaves will begin to emerge.
With assist, plumeria can last winter indoors.Chicago Tribune January 10 2014. https://articles.chicagotribune.com/2014-01-10/classified/ct-home-0110-garden-qa-20140110-1_1_plumeria-plants-winter-indoors
Overwintering Plumeria in a Cold Climate https://www.youtube.com/watch?v=g7u1WFmIWeo
Missouri Botanical Garden. How do I care for my plumeria? https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/gardening-help-faqs.aspx?questionid=96&afmid=4462
Southern California Plumeria Society. Winter care. https://www.socalplumeriasociety.com/winter-care
Lawder, S. Plumerias: growing in cold climates (slides) https://docs.google.com/a/socalplumeriasociety.com/viewer?a=v&pid=sites&srcid=c29jYWxwbHVtZXJpYXNvY2lldHkuY29tfGhvbWV8Z3g6N2EzNTI1OGZmYjc4ZTRmNQ
University of Hawaii. CTAHR. Plumeria. https://www.ctahr.hawaii.edu/oc/freepubs/pdf/OF-24.pdf