It’s not a good idea to connect Hue bulbs of any type directly to the smartthings hub as they can mess up your zigbee mesh. It’s much more reliable to use them with the hue bridge.
Yes. The only officially recommended way to use Hue devices with SmartThings is by using a Hue bridge.
There are several reasons to use the bridge.
Other Integrations
There will be a number of other integrations available to you which you may want to take advantage of.
Use of Hue Scenes
you will be able to activate scenes created with the official Hue app, which at the present time offer many features not available in the smartthings scenes feature. Even just the ability to blink the lights. The easiest way to access scenes from the Hue app is through the following custom edge driver or IFTTT, but there are other ways as well.
[ST Edge] Philips Hue LAN [BETA] (3rd Party Driver, Not ST Native)
Not using the Bridge can mess up your zigbee network
the most important really is …