Answer: Gladiolus are not winter hardy, so they are planted in the spring for bloom during the summer. They are replanted each year, or are dug and stored indoors each winter.
Tulips are planted as bare bulbs in the fall for bloom the next spring. Some varieties are longer lived in the garden than others. Cottage tulips for instance tend to perennialize well. For best results, tulips need full sun and well drained soil. In the spring, leave the foliage intact until it turns brown and dries up. This process replenishes the bulbs so they can bloom again the following year.
In your area with its cold winters, yucca would be better planted in the spring. If you are not able to find any locally, you might try mail order sources such as
or Wayside Gardens http://www.waysidegardens.com
Best of luck with your flowers!
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