Answer: Northeastern Kansas is in USDA growing zone 5, so in late April, tulips should still be blooming. I'm not sure about the southeastern corner (Zone 6), but you can delay the emergence of the tulip plants by planting the bulbs in a bed that remains cool late into spring, but still receives plenty of light. If you get snow in your area, a pile of snow heaped over the planting bed, and covered with evergreen boughs or sawdust, will keep the tulips in "cold storage" until you want them to grow. Remove the snow from the area about 4 weeks before you want them to bloom. You may also want to try some later-blooming daffodils and even anemone -- beautiful! Contact mail-order bulb suppliers for their catalogs to research which varieties will likely bloom towards the end of April in your area.
I always recommend that wedding planners have a florist as a backup, just in case nature doesn't cooperate with your timing. Fortunately, tulips will still be widely available throughout the country at that time, so if your bulbs don't come through for you, a florist still can.
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