You can use half of a wine barrel as you will see in the tutorial below, The green and flowers will not only look good, but give you fresh breath and good mood.
Tutorial Via Instructables
You can also use a different container such as this terra cotta clay pot. Any container will do for as long as it’s large or deep enough to hold the umbrella securely in place and meet your personal favorites.
Tutorial Via h2obungalow.com
And you don’t need to use it as umbrella stand only, you can make a lamp or a hanging basket with a pole instead as following. You can make a study planted post using a wine barrel and a wooden pole at its center. So beautiful to make and be used as outdoor lighting features at night.