Hello, How great to have such a nice surprise! I am not entirely certain what happened to cause the plant to grow so much. The celosia can grow on average 24-36inches tall. Is that about how big yours was? There could be something in the soil or just our unusually wet weather. I wish I had more information to offer. I did some checking and couldn’t find any explanation but that other gardeners have had 36plus height. Here is a site that you can review more details for the celosia plant. https://plants.ces.ncsu.edu/ I hope this helps. Please let me know if you have any other question.

Ours was 24 inches.  It was just planted with other plants in a planter.  Just regular garden soil.  The interesting thing is that this plant grew from a seed of the original, small plant!

Hello!

Celosia is easy to propagate. In fact, it is self-seeding and spreads over the garden effortlessly during growing season. It will only grow for a year and the key to growing healthy, vibrant Celosia is rich, loamy and well-drained soil. You must have just the right soil.

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