Start or add to your citrus orchard this month when conditions are generally ideal for planting. Oranges, lemons and limes thrive throughout the county; grapefruit and tangelos do best inland. Pick varieties hardy in your area and plant in full sun in well-draining soil. Dig a hole as deep as the root ball, but twice as wide to encourage wide ranging feeder roots that grow close to the ground's surface. After citrus is planted, proper irrigation is key. The root ball needs to be kept moist until roots grow out into the soil. But over watering can cause rot and other diseases. Start by watering at least once a week, more often in times of extreme heat or dryness. Increase the interval as the tree matures. As the trees grow new leaves or blossom, adequate regular watering also can help prevent leaf and blossom drop. Regular water too helps prevent fruit splitting in navel oranges that commonly occurs in fall. How to judge water needs? Check moisture levels about 2-inches below the surface. When dry to that depth, water again.