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Most growing plant organs move with a period that ranges typically from minutes to several hours. This phenomena is the growth-dependent oscillation of essentially all plant organs. The movement, called circumnutation, is generally not perceptible under normal viewing conditions but can be observed in time-lapse photography. The objective of this study is to explore whether time-lapse photography of circumnutation can be used to assess plant vigor. Tomato seedlings grown under controlled-environment conditions were set in a growth chamber at 25 0.5 C and plant images were acquired by a remote-controlled digital camera at 5-min intervals for 2 days. The images obtained were used to determine the properties of the circumnutational movement and daily leaf growth rates. During dark periods, vigorous circumnutation movement of shoot tips were observed in all monitored seedlings. There was no close relationship between oscillation period or amplitude, and leaf growth rate, whereas maximum speed of movements in a night linearly increased with daily relative leaf growth rate. The number of plants in a pot did not affect the movement properties, implying that circumnutation was not influenced by planting spacing. These results indicated the potential use of circumnutation for assessing plant vigor, however, the relationships between growth rate and circumnutational parameters were not simple.