2023 Volume 22 Issue 2 Pages 141-154
In Japan, gosun (six-inch) carrots are produced using the well-established relay cropping method across various production areas to ensure that they can be supplied throughout the year. On the other hand, mini carrots cannot be stably supplied throughout the year. Mini carrots are grown according to the cropping type of gosun carrots and are distributed throughout Japan, and there are no standards of shipment. To examine the possibilities of year-round cultivation of mini carrots in a region with a temperate climate, we planted mini and gosun carrot seeds in the same region a total of 20 times over 4 years. The growing period (growth rate) of mini carrots in the warm region of Japan varied with each sowing time. Except for sowing from October to February, the fresh weight of the underground parts reached the standard for shipment by 110 days after sowing. The minimum fresh weight of underground parts required for shipment is 10 g for mini carrots and 70 g for gosun carrots, and the growing period to reach this standard requirement was shorter for mini carrots compared with gosun carrots. However, in the low-temperature season, the growing period required to reach the standard was longer than that on conventional sowing in April. Therefore, the possibility of year-round cultivation of mini carrots was suggested using heat-retaining materials and adjusting the planting density to shorten the cultivation period.
