Techniques for measuring time-varying biospeckle of botanical specimens are investigated. Experimental evidence on the probability density function is presented. Several applicable techniques, such as power spectral density and correlation, are used for measuring and analyzing the temporal speckle intensity variations. These techniques are shown to exhibit information about the shelf life and aging of some botanical specimens used in our study. We also present a new phenomena related to the spatial properties of time-varying speckles. Theoretical and experimental results on the size of a speckle in a speckle pattern and its relation to the temporal intensity variation are also detailed.