Late summer might not seem the time that thoughts should turn to seed sowing and propagation, but if you want to grow any out-of-the-ordinary species next year it may be time to order the seeds now.
There's nothing more frustrating in early spring to find those exotic seeds you've just received come with growing instructions that require them to be 'stratified' for several months to break dormancy.
This usually means a long period of refrigeration to fool them into thinking they've been through a cold winter, so they'll be ready to burst into life when you eventually put them into warm soil.
Some may even need an initial warm spell before they experience the cold, and then they'll germinate in the warmth again next year - in this case, first keep them somewhere warm in the house for a few months before popping them in the fridge.
If you leave the seed ordering until next year, it means they may not be ready for sowing for a long time, and then it could take a couple of months afterwards before they even germinate, so you've effectively lost a whole growing season. Any seedlings sown later in the year might also not have enough time to become properly established before the cold weather arrives, which could easily kill them off.
So get thinking now about those trees, shrubs and palms etc you want to start off next year, research their propagation requirements on the internet and if necessary order the seeds soon.
When you receive them they can go into the fridge over the winter, you can forget about them for six months and they'll be ready to sow indoors early next year.