When you get ready to plant your urn up with greenery for the holidays, you can plant the mum and the coral bells in the ground. They are perennials and will come back year after year. As a matter of fact, I have quite a few patches of coral bells throughout my flower beds. They all started in fall planter planters, moved to the flower beds after Thanksgiving and then start reproducing themselves from there. Celosia is a tender perennial and usually grown as an annual in my part of the country. Unless you live in Zones 10-11 (basically the southern tips of Florida and California) they won't be able to survive in the ground in the winter. You can try to dry the plumes if you wish for dried flower arrangements though. Flowering Kale (aka Ornamental Cabbage) will actually last fairly long, possibly throughout the winter, although the stems tend to get very long and the plants lose their attractiveness after a while (they have their best show of color in full sun in the late summer and early fall). Most gardeners treat these as fall annuals and toss them after fall and start anew the next year. Pansies can go either way. Most people plant pansies as annuals only in the spring or the fall. They really enjoy the cooler temperatures. Although pansies can survive a frost and even harsh winter weather and possibly still bloom again in the spring, it's not a sure bet. You might want to try to overwinter them in the ground and just see what happens.