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The timing of seedling emergence may strongly affect fitness in competitive environments. Therefore, selection should favour mechanisms that allow sensing neighbours prior to emergence. We tested whether or not germination is affected by density and identity of neighbouring seeds or seedlings of desert perennial plants. Based on theory, we predicted that germination fractions are independent of neighbouring seeds, that germination is accelerated in dense interspecific neighbourhoods, and neighbour effects are caused by seedlings, not by seeds. We examined germination fraction and timing of four naturally coexisting sandy desert perennial species in low versus high seed densities in both intra‐ and interspecific neighbourhoods, and with and without removal of newly emerged seedlings. Neighbours accelerated germination independent of density and this pattern was apparently caused by the presence of early emerging seedlings. Germination fractions were lower in high seed densities even when neighbours did not germinate, indicating that seeds were able to sense each other prior to emergence. Early germination may be adaptive because fast emerging seedlings may gain a competitive edge over slow emerging ones. However, since seeds that did not germinate died, delayed germination may only be advantageous for mother plants when sib competition is intense. Another key finding was a competitive hierarchy with late successional species germinating faster and inhibiting germination of pioneer species. This indicates that successional processes may be directed as early as during germination.

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Native plants are increasingly used for revegetation and restoration. These plants are cultivated for several generations at plant nurseries and often they are of unknown provenance. Therefore, cultivated plants often differ from their wild progenitors in life-history traits. Using germination behavior as example, we tested the assumption that cultivated plants have different life-history traits than their uncultivated progenitors. Cultivated as well as wild individuals of Plantago lanceolata and Lotus corniculatus, two species frequently used in revegetation, were tested in a common garden experiment as well as in incubators for their germination behavior. We observed significantly faster and more abundant germination in cultivated varieties. Using artificial crossings, we found that also hybrids of cultivated varieties and wild relatives germinate faster and more abundant than the wilds. As wild plants acquire their life-history traits by natural selection, we have to assume that they represent the optimal adaptation to the environmental conditions. If these traits are changed by cultivation or by hybridization between cultivated varieties and local populations, the long-term survival probabilities of local populations may be altered. Therefore, the use of cultivated varieties of native plants should be avoided in revegetation.