Calamondin Orange Bushes are one of the best indoor fruit trees. The fruits change from deep green to bright orange. You'll usually see flowers and fruits on the tree at the same time, making it a fresh, colorful accent for a sunny room. There is no hurry to pick the calamondin oranges off the tree - they last long and you can enjoy them for months. Allow the soil to slightly dry in between thourough waterings. They like a sunny spot.