Without further ado, then, here are some questions to think about; you don't have to answer them all or in any order, certainly -- they're just some thoughts to get the ball rolling.
How important is the idea of "nature" within your religion?
How is nature conceptualized within your religion?
How does nature -- concepts, imagery, attitudes toward -- function within your religion?
Where do things like agricultural festivals fit into your religion overall?
If you practice magic, how is nature figured -- is it *the* source of power, *a* source of power, totally irrelevant, what?
I have difficulty pinning down answers to things like these, probably in part because I'll admit I've gotten caught up in the "AM NOT!" "ARE SO!" thing and thus have maybe not spent as much effort as I should have on really examining the role nature does or does not play in my religion beyond "it's not central". My answers may not, therefore, be as coherent as I'd like.
My initial thought, though, would be to say that there are elements of nature in my religion. There are plenty of deities whose sphere of influence includes natural things. Some are really obviously tied to the sorts of things one stereotypically thinks about when one thinks of religions that feature nature; Demeter with the harvest and grains and stuff or Artemis with the wild things, for example. Others aren't maybe what immediately comes to mind with the "nature" stereotype, but are associated with bits of nature nonetheless; Zeus and storms, Apollo and the sun, even Hades and death. But then you also have, say, Athena and civilization, Ares and war, Hera and marriage, Hephestios and craft. There's nature there. There's also plenty of non-nature.
As for festivals, I haven't dug into Hellenic festivals as much as I'd like, but I'm sure there's probably a harvest festival or a planting festival or something in there somewhere. The cycle of the seasons is not a focus itself, though. (In fact, the calendar we discussed a while ago in the Ta Hiera SIG for Reform Hellenic Reconstructionism had nothing at all to do with natural cycles.) My sort of vague understanding is that a lot of Hellenic Recon practices today are based on what we know of ancient
Athens, though, rather than the ancient Greek countryside. Looking at it from the context of a city, it makes sense to me that festivals related to food production that's happening way out in the country would not be as prominent as festivals geared toward things that were happening in the city.
For having not much to say, I sure am babbling a lot... *sigh*