Optimizing Soaking Time for Enhanced Microgreen Growth in Arugula (Eruca sativa Mill.)

Abstract

This study explores how different soaking durations influence the germination and growth of
arugula (Eruca sativa Mill.) microgreens. Known for its rich nutritional profile, distinctive flavor, and
numerous health benefits, arugula is a popular choice for microgreen cultivation. In this experiment, we
soaked the seeds in water for varying durations ranging from 0 to 72 h before growing them in a
vermiculite medium under consistent light and irrigation conditions. The findings revealed that seeds
soaked for 0 h exhibited the highest germination rate, maintaining a strong viability of approximately
85% to 90%. When the soaking duration extended to 6, 12, and 18 h, the germination rate showed a slight
decline. However, a more pronounced reduction was observed after 24 h, and by 72 h, the germination
rate had dropped significantly to around 65%. Beyond germination, the soaking duration also affected
microgreen growth. The tallest microgreens, reaching optimal heights, were produced from seeds soaked
for 0, 6, and 12 h. In contrast, seeds subjected to the longest soaking time of 72 h resulted in the shortest
microgreens. These results suggest that prolonged exposure to water may impose stress on the seeds, as
evidenced by the reduced germination rates and shorter microgreen heights observed, ultimately
hindering their growth potential. Overall, the study highlights that while short-term soaking (up to 12 h)
has little effect on germination or microgreen development, extended soaking times-especially beyond 24
h-can negatively affect both processes. To maximize growth efficiency, soaking arugula seeds within the
0-12 hour range appears to be the most effective approach.