Lavender oil has a shelf life of up to five years. The shelf life can be determined by outside factors such as how it is stored and the temperatures. Always store lavender oil in a dark, cool place. It doesn’t respond well to drastic temperature changes and the sun’s ultra violet rays can damage the oil. This is why most essential oils are packaged in dark brown bottles. If the oil has become thick or cloudy, it is probably safe to say that it has lost its therapeutic properties.