They did try to capture the Caucasus oil fields in 1942, it was one of the main objectives of Operation Edelweiss, which was a subsidiary of Fall Blau, the great summer offensive of 1942. The main goal of Edelweiss was to capture the Caucasus oil fields at Grozny, Maykop, and Baku . The Germans prepared a special engineering brigade that would wait in the wings to restore oil production for the Reich once these oil fields were captured, as well as special forces to prevent Soviet destruction of the facilities.

Yet these efforts were for naught. Of the three main oil objectives, the Germans only captured one, Maykop, in August. Not only was the Maykop the least significant of the oil fields, but Soviet demolitions were quite thorough enough to be termed by one German commander "a classic example of fundamental destruction." The German offensive towards the rest of the oil fields stalled out in August, especially as the Stalingrad battle to the northeast ate up reserves, and more importantly, airpower. This meant that the subsequent German advance in the Caucasus ground to a halt and OKW suspended most Caucasus offensive operations in October. When it became clear that the Germans would not gain the Baku and Grozny fields, Hitler authorized a bombing offensive against Soviet oil facilities in September 1942, but this achieved only meager results.

The belated air campaign against Soviet oil underscores the problematic approach German strategy took towards Soviet oil. The idea that this oil was fundamental to Germany's future warmaking ability was central to German planning. Hitler told his generals at Poltava in 1942 that "If I do not get the oil of Maykop and Grozny, then I must end this war." This constrained Germany's offensive into the Caucasus because it predicated much on the speedy capture and exploitation of the fields. But as Maykop's fate illustrated, oilfields could be easily sabotaged prior to capture. Terrain and other geographic impediments also made a swift coup d'Main of the Caucasus exceedingly unlikely. By the time it dawned on the German command that the fields were out of reach, their main weapon to deprive the Soviets of the oil facilities- the Luftwaffe- was very much overextended and worn out from extensive operations in the Crimea and covering the growing Stalingrad debacle. Moreover, Soviet resistance was much more capable than it had been in 1941 and the type of massive operations netting huge numbers of prisoners was not something that happened in Blau. While there were some initial successes, they were not on the scale of the prior campaign and Soviet resistance was much greater than before.

Sources

Citino, Robert Michael. Death of the Wehrmacht: The German Campaigns of 1942. Lawrence: University Press of Kansas, 2007.

Militärgeschichtliches Forschungsamt. Germany and the Second World War: Volume VI- The Global War. Oxford: Clarendon Press, 2001.