Blooming seasons for ‘Marsh Seedless Grapefruit’, the variety you most likely have since it’s the most popular, is from November through May. Marsh has a tendency to hold it’s fruit on the tree for long periods of time, taking as long as nine months to ripen. Available year-round with the peak from January through April. Florida and Texas provide the bulk of the winter crop while Arizona and California produce the bulk of the spring and summer supply. Because of these extended periods of time, November through May, and spring and summer, it is very likely that one individual tree may bloom more than once, and at different times, depending on the environment and the ‘mini-climate’ the tree is grown in. Grapefruit can have a number of interactions with certain medications, so if anyone in your family is taking prescription drugs, please go on-line and check that list