There are still plenty of flowers to see, and the Douglas Justice's September blog has lots of good photos of them - September 2021 in the Garden - UBC Botanical Garden. I definitely recommend checking it out. I'll start with some plants I checked out because of the blog. The first one mentioned is Helianthus angustifolius - the attribute in the name means narrow-leaved, so it was easy to identify. Next to this bed is Hylotelephium 'Herbstfreude', commonly called Sedum autumn joy. I posted the two Hylotelephium elsewhere on the forums last year, as Douglas wrote about them in the August 2020 In the Neighbourhood - UBC Botanical Garden blog. He mentioned there that this one has alternate leaves. Autumn joy also blooms a little later than Hylotelephium spectabile Brilliant Group, which is on the other side of the plaza, surrounded by autumn joy. H. spectabile has opposite leaves, and its flowers are fully open. It's easy to tell them apart right now - you can see the difference in colour in the first photo below. I've posted Rosa x odorata 'Mutabilis' many many times. There are still flowers. It was mentioned somewhat in passing as being in the same bed as Strobilanthes attenuata.