A soil conditioner apparatus and method condition soil for compaction. The conditioner apparatus creates a heated stream of air directed toward the ground as the conditioner moves along the ground. A mixer on the conditioner mixes soil in the path of the heated air to dry the soil. Some embodiments of the mixer will propel the soil into the air in the stream of heated air. The conditioner can decrease moisture in the soil in the location where the soil will be compacted. In some embodiments, ambient air is introduced into the conditioning process by additional blowers. The mixer can also mix added soil and other additives to the soil in location. The conditioner apparatus may take the form of an apparatus towed by another vehicle, a set of towed apparatuses, an apparatus carried by another vehicle, or a self propelled vehicle having the operational elements of the soil conditioner.