The couple began growing the giant vegetable in April last year at their eco-tourism guesthouse.
Speaking to CNN, Norwood said while it did not always succeed, she attributed the success to a good, wet spring, good rainfall and hot weather in the early summer. The couple also pruned nearby cabbages to allow the mammoth vegetable to grow at its own pace.
The couple kept hungry pests like wallabies and possums out with a wire fence, and had to place the cabbage under a fine net to stop slugs and butterflies from invading it. The cabbage ended up large enough to provide almost two weeks' worth of food, they said.