For Goodgym I was the only one who turned up, but there ended up with a good 10 people or so, all willing to plant some trees.
After a bit of training, we got on and planted some trees. The first hole I dug, had bricks in it, which was a pain to shift, then tree planted and mulch was added.
When trying to dig a hole for the second tree, I developed some back pain, sitting down for a while didn't help, so I cycled home and left them to it.
For future reference the Redbridge Conservation team did provide some gardening gloves and had a tea/coffee break.