Cucumbers come to harvest quickly. Six to seven weeks after planting, small cucumbers will begin to form. Pick the first cucumbers small; this will encourage the plants to produce more. When to Harvest Cucumbers Cucumbers can be harvested as soon as they are edible size. Harvest slicing cucumbers when bright, green, and firm and 6 to 8 inches (15-20 cm) long. Harvest pickling cucumbers when 2 to 4 inches long–6 to 7 inches long for big pickles. Harvest lemon cucum
