Me he expresado mal en lo de "necesidad de estratificar". Quiero decir que las semillas de algunas especies necesitan del proceso de estratificación para que germinen. Pero las semillas de esas especies si no se estratifican también germinan (sobretodo si son frescas) aunque en mucho menor porcentaje. Ya te diré lo de la humedad de la nevera.
En referencia a la estratificación, los de bestcarnivorousplants dicen lo siguiente: "Seed are sown on the surface of moist planting medium, the "wet method," in prepared pots. These pots are then placed in a warm area (around 20°C) for 1-3 days. Then the pots are placed in the refrigerator (0-5°C) for 6-8 weeks. It is necessary to control the spread of molds, which we do by dusting the seed with a fungicide. After this time we remove the pots from the refrigerator, put them in a bright place, and then treat them like other seeds that do not require stratification. The so-called "dry method" gives the worse results. This is when dry seeds are put in paper bags and stored in a cool area at 0-5°C for 6-8 weeks" En concreto de las semillas de sarra dicen: "Sarracenia seed require a cold treatment before they are capable of germinating. These methods have already been described above. Utilizing gibberellic acid results in a high rate of successful germination. There is another interesting method useful for germination of seeds from this genus. Put the seed into a small plastic bag, adding water to the bag before placing it in the refrigerator for 48 hours. I do not know if this procedure is useful for all species or to what degree it is successful. Seed are sown on the surface of the moist planting medium (peat moss : sand at 3:1) at temperatures of 18-28°C and 60-100% relative humidity. Seeds germinate within a few weeks or over a period of several months, but can take as long as 1-1.5 years. You must begin to harden the young seedlings after several weeks, with careful ventilation being best. Seedlings can be transplanted when they have produced 2 or 3 leaves (traps). I have made an interesting observation about the seed of S. purpurea ssp. purpurea. The seed, which had germinated during the past year, being sown on the surface of living sphagnum in spring, were left in the garden exposed to the vagaries of weather during winter. The seed germinated during the next spring" Para cada especie de sarracenia, la web francesa plantescarnivores dice los siguiente: "Stratification : Placer les graines sur (et pas dedans) le substrat définitif, maintenu humide comme une plante en pleine période de croissance, et placer le tout au réfrigérateur. Les espèces exclusivement sudistes (S. alata, S. leucophylla et S. psittacina) ne réclament que 2 semaines. Plus de temps n'augmente pas le taux de germination, voire même le fait baisser chez S. leucophylla. Les espèces intermédiaires et plus rependues auront les meilleurs taux avec 4 semaines de traitement Seul S. purpurea ssp. purpurea obtient ses meilleurs résultats avec 6 semaines de traitement (adaptation aux rigueurs du climat)."
En resumen las semillas deven de ser eztratificadas con humedad, tambien dice que el uso de acido gilbertico (no se si asi se llama) da un gran aumento en la germinacion. Dice que el metodo de estratificar las semillas en seco (sin ningun sustrato y nada de humedad, solo las semillas en un sobre plastico dentro de la nevera) ha dado los peores resultados. GRACIAS SALUDOS
