The area by Childeric Rd, slated to be a wildlife zone, was covered with dense stands of tall Goosefoot species, but threw up this Jersey Tiger - a moth increasingly found in the capital (I saw two last year). Apologies for the poor picture quality, but it's good enough to show that's what it was .....
Amongst various common weeds of south east London, including Black Horehound, Yarrow, Hedge Mustard, Knotgrass and Black Medick were Woody Nightshade, Sun Spurge, Hemlock and the less frequently seen Field Pennycress.
The best botanical find was this Dark Mullein (Verbascum nigrum), my first (apparently) non-planted find in London - though I have seen it in a Bexley Council flower bed, so you never know .... It had a specimen of the bug Liocoris tripustulatus on it.
There was also a Stinking Iris outside the park fence.