Most seeds of high-alpine plant species are very small, typically ranging from 0.5 to 2 mm in diameter. Despite their size, they securely encase the embryo within protective seed coats or fruits, allowing them to withstand harsh environmental conditions and ensuring both survival and successful germination. Because these seed coats must function as effective barrier materials while remaining extremely thin, they may offer valuable inspiration for the development of more sustainable packaging solutions.

We analyzed seeds from multiple alpine species using microcomputed tomography (µCT), focused ion beam–scanning electron microscopy (FIB SEM) under room temperature and cryogenic conditions, classical histology, and scanning electron microscopy with energy dispersive X ray spectroscopy (SEM EDX). Our multiscale analysis reveals the intricate morphology, composition, and potential functional properties of these natural barrier structures, that differ enormously from species to species. We show that testa thickness varies between species from 10 to 150 µm and may consist of multiple layers with distinct chemical compositions and mineral contents.

These first findings provide new insights into the morphology and composition of alpine seed coats and allow the identification of candidates that can serve as inspiration for the design of novel, sustainable packaging materials.