As part of Science Week (6-15 March), the British Science Association is giving away free seeds for bee-friendly plants. You can order your packs from www.saveourbees.org.uk, then find a space and plant them!
This is a nice website: it has a specific purpose and does it well. There’s also good feedback on the site activity and I see that in the last 10 or 15 minutes there’s been about 50 new orders.