On 26 August the two ships parted; "Alert" continued to push north while "Discovery" waited in reserve. Ninnis' biological work then extended to horticulture. He collected wheat seeds left in the area by the Polaris expedition four years previously, and planted them—together with mustard, cress and pea seeds—between the decks of the "Discovery". In May of the second year they were transplanted to the shore, under glass. According to Robert Johnston, in his 1877 summary of the expedition, "This experiment succeeded very well; but, evidently, such an attempt at fancy gardening, under difficulties, could not be relied on to supply the wants of an entire ship's crew."