Just after the final frost left the ground and before rows of vegetable and root plants were planted in the Old Amana gardens, gardeners would place small setups in the garden called "cold frames". These were usually built by the carpenters in mid February from wood planks and propped by bricks, then covered with wooden storm windows. This created a greenhouse effect, kept the soil moist and allowed for the early sowing of seeds. Fertilizer was also added to enhance growth of seeds and plants. Kitchen and garden bosses of the old community kitchens would be anxious to get these going in the spring. These cold frames were covered on cold nights and propped open on warm days for airflow or ventilation. In this way the gardeners could strive for an Easter harvest of lettuce and other greens which could be picked longer this way than in nature. This method is still used today in some Amana gardens.