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The tenacious, dry bracts constituting the coverings of seeds of the Namib desert gymnosperm, Welwitschia mirabilis, have been shown to impose a constraint on germination rather than this being a case of physiological dormancy. Removal of these structures without any other treatment enabled rapid germination, whereas soaking the seeds either with the coverings intact or removed, resulted in poor germination. After removal of the coverings, seed samples with a low proportion of individuals infected by Penicillium crustosum responded well to treatment with a commercial fungicide (Sporekill(R)), which eliminated the fungus, whereas surface-sterilisation with sodium hypochlorite was extremely damaging. This fungicide, however, was ineffective when the seed-associated fungus was Aspergillus niger var. phoenicis. Germination performance of the seeds was unaffected by their maintenance at 80degreesC for 48 h, establishing both their highly orthodox nature and possibility of ultra-dry storage, as well as a potential means of thermotherapy. Preliminary trials established that W mirabilis seeds at the water content at which they are shed have the potential to be cryopreserved. Seeds from which the coverings had been removed not only survived immersion in liquid nitrogen, but also achieved undimished germination totality far more rapidly than did the equivalent, untreated sample. The present work has established the basis of guidelines for the practical handling of W. mirabilis seeds and hence conservation of this unique species.