Panicle Hydrangea 'Limelight' on stem White - Hardy plantCream coloured plumes on a stem. The panicle hydrangea 'Limelight' (Hydrangea paniculata) is pretty as a picture. Place the plant in a pot on the patio. The flowers bloom in the summer. The plant is reasonably winter hardy. The standard hydrangea does not require pruning. You can choose to cut off any protruding branches. Place the plant in full sun. Water the plant sparingly. Water it more during dry periods.