This one by Paghat is exceptional.
It has such very good reviews of each plant they feature that it qualifies for an entry in Resources section
http://www.paghat.comPaghat is based in the Pacific NW area of US, and the climate there is as near as you'll get to some parts of the UK, so the info is quite relevant. Their Flowering time may be a bit earlier than UK - they have this elusive thing called full sun earlier, hotter and longer than UK.
When I'm researching plants for the Master Database, this one comes up regularly, and I find most of the info I need in one site.
I usually place a link to the web page in the Plant Data for the plant being researched.
The next issue of the Master Database will have quite a lot of new stuff!
