I agree. I fond the climate zones actually to be kind of worthless too. Because every year is different. We had a zone 10 winter this year. And we are in 9A. When the climate maps got redrawn this time, we remained in 9A, while Houston TX was moved to 9B. We are at the same latitude. And while they were absolutely decimated by the polar fronts that moved through there in 2021 ands 2022, we were almost untouched here. So how are they 9B, and we aren't?
Last summer, my town broke the record for the most days over 90F, ever. I think we may have only had 2-3 days UNDER 90. We usually think of October as starting to cool down. But the 90's ;asked into November last year.
I think a good rule for everyone to follow is...research the specific plants you are thinking of planting in your garden, or keeping in your greenhouse. I desperately would like to grow some of the very large leaved/large flowered Pleurothallis orchids in my greenhouse. Ones like P. gargantuan. teaguei, P. titan. But I am hesitant.
I grow a miniature, P. grobyi, that I have had out there for 15 years at least. Even though all these orchids are the same genera, Pleurothallis, some are more heat tolerant than others.
P. grobyi will take a minimum of 40F, while it can take max temps of 95F.
The others I mentioned need warmer nights (around 52-55) and max out in heat tolerance around 80F. Since its routinely 85-90F in my greenhouse, the heat might kill them, and since they aren't cheap, its a risk.
Its the same with flowers and trees in the garden. We have always been told that we are too cold for Tabeuia trees here. Yet, there are scattered specimens growing in peoples yards, both pink and yellow, that have been there for decades. Literature says they need a zone 10 climate. So they shouldn't grow here, right? yet, there they are. If you do your own research, you are much more likely to find things you can reliably grow in your yard than if you rely COMPLETELY on published data. I use that as a guide at best
