Yes, the nights are getting chilly here in upstate New York bring good germination of the South African wintergrowing species, and a good indication that now is the time to get the Australian tuberous species going again. I have returned my tuberous species to cultivation: watering the pots that have stood dry all summer from the top, and allowing the medium to be only slightly moist at first. As the frequency of cool days increases, I will increase the watering, but right now the tubers are in a sensitive phase, and I don't want them to rot.
Since the tuberous seed needs temps around 45F for good germination, I have sown the seed now as well, figuring that by the time the cool weather hits here in another month, some of the inhibitory auxins will have leached out of the seed coat, enhancing the chance of germination. Peltata and auriculata seldom are difficult, and I have sown many varieties acquired over the summer not that fall approaches.
I planted some tubers today, all of which are showing signs of growth. It looks like I will finally meet Drosera menziesii ssp menziesii and get to shake tentacles with it! This species has some of the most beautiful flowers in the genus.
I also look forward to Drosera whittakeri ssp whitakeri the "scented sundew"
So if you have tuberous droserae seed, I think now is the time to sow it. This year I am going to try fire stratification with some seed. As I understand it, this requires a hot, quick burning: not prolonged baking. In habitat, the fire ecology is a vital part of the tuberous droserae cycle. In habitat, the remains of the stem and leaves of summer dormant plants dry out in the long, hot, dry summer. When lightning strikes the land and generates a fire, the fire sweeps through their very fine and dry leaves in a flash, and quickly moves on. I speculate that the seed remaining in the pods is that which gets the significant stratification, and falls to the ground which is now clear of other vegatation with which it would compete. I figure I will use dry grasses, and other fine dry material to get a hot quick burst of flame on top of the pots where the seed is sown. Then I will allow the pots to sit with smouldering leaves placed on top of a little lit charcoal inside a barbeque with a lid. This way the smoke will be thick, and will condense on the surface of the pots. Maybe this will do the trick! My experiments with GA3 last season were less than encouraging.
I also plan on incorporating some ash into my mix to see if this has any effect on germination and subsequent growth. I have heard from friends in Australia that this greatly increases the tuber size in a season.
A side note: if anyone purchases tubers from Australia in this season (i.e. from Lowerie) be aware that tubers are now being harvested there as the plants go dormant. These tubers must be acclimated to this hemisphere as the seasons are reversed, or they will not grow and will rot if planted now. I learned this one the hard way!