The possible period for trekking in Sahara starts in October and lasts until the heat strikes again in April. This is also the least dangerous period when it comes to avoiding sandstorms. However, the best time is December through February when the temperature is the mildest. Late February or March is also beautiful in desert, since the amazing sight of flowering plants at the base of the dunes will definitely bring colour to your experience. However, beware of the sandstorms that can happen any time of the year, but most probably in the end of March and into April.