SmartThings sync with Hue

I have a SmartThings set up with Philips Hue and a Nanoleaf Canvas. An automation routine turns the Canvas on when the Hue bulbs are on and off when they’re off.

This works OK from the SmartThings app, but when the Hue bulbs are turned on in other ways - through the Hue app, or from a Hue Button - the automation doesn’t work.

Basically SmartThings isn’t seeing the status of the Hue bulbs. If I check the “linked services” in the SmartThings app the automation suddenly kicks in. So it does sync at that point. Just not automatically/periodically.

Doing some reading, I believe SmartThings is meant to sync statuses from the Hue Bridge. I’ve read mixed reports on whether it does this every 5-10mins or every 5secs, but no matter how long I leave it, I get no sync unless I check the Linked Services.

I don’t have a SmartThings hub - is one needed to do this sort of thing? ie if I had a SmartThings hub along with the Hue Bridge etc, would it sync bulb statuses quickly and let the automation work. Is what I’m trying to do achievable?