Mandevillas ready for outside
I brought two beautiful Mandevillas inside in October. One struggled and eventually died. The other did okay until recently and is now looking straggly. Is it okay to take them back outside. I only remember frost a few times this winter and very little “freezing” weather. Some nights last week were cold. If I do take them outside soon, should I try to cover them with plastic at night. Thanks very much.
District of Columbia County District of Columbia
Mandevilla is a tropical plant with minimal cold tolerance - not just an intolerance for freezing temperatures. They should not go back outside until around mid-May, when all danger of late frosts (and cold nights in general) are behind us. You can attempt to put them out sooner, such as late April, but use caution and bring them inside if the evenings dip below 50 degrees F. A plastic covering might not trap enough warmth and the poor air circulation inside of the cover could promote fungal growth.