On imbibition the seeds of certain species form a polysaccharide hydrogel, termed mucilage. In Arabidopsis thaliana and Camelina Sativa, this mucilage is composed of 2 layers, the outer being water-soluble while the inner is tightly attached to the seed surface. Determining the macromolecular properties of mucilage polymers in the inner mucilage layer can only be achieved in situ as detaching the polysaccharides involves breaking them either by physical or enzymatic methods, which alters or eliminates their structure. It has already been shown that the physicochemical properties of mucilage polysaccharides affect accessibility and mobility of molecules within the hydrogel. In order to compare inner mucilage properties between species, we have developed methods that can be applied to intact seeds. We have used low-field nuclear magnetic resonance (NMR) spectroscopy to characterize water uptake and mobility in Arabidopsis thaliana intact seeds based on T2 relaxation times (Saez-Aguayo et al. Plos Genetics, 2014). In imbibed seeds, five T2 components were identified which could be assigned to protons of various water populations with different mobility and ratio depending on their localization in seed tissues and mucilage layers. Analysis of the evolution of signal amplitudes for the different components allowed the water transfer rates between different compartments to be determined. Calculation of water content for each compartment confirmed that even after 24 h of imbibition, approximately 40% of water associated with wild-type seeds was trapped outside in mucilage. Surprisingly, despite released mucilage being an excellent hydrogel, it did not increase the rate of water uptake by internal seed tissues and is more likely to play a role in retaining water around the seed. In order to localize the different tissues and the inner mucilage layer, we analyzed Camelina sativa seeds which are bigger making possible their characterization by magnetic resonance micro-imaging and this is compared to analysis of mucilage properties using fluorescent recovery after photobleaching (FRAP).