What’s in a bulb?

Mon. Mar. 5, 2018

Click below to listen to my 2 min. Garden Bite radio show:  What’s in a bulb?

What’s in a bulb? Is it really a bulb? Is it a rhizome? Is it a corm? Is it a tuberous root? And what’s the difference? Let’s start with what they have in common. They’re all underground storage units.

All the things they need to sprout and flower are stored in their fleshy structures underneath the soil.

from the University of Georgia


Here’s another look from my friends in the U.K.!

Rhizome etc.

Bulbs etc. written

Once their leaves are up and at attention, those leaves will manufacture the food that will be sent back down to those fleshy structures underground for storage for next years flowers.


  • Bulb – tulips, daffodils, lilies, amaryllis
  • Rhizome – bearded  iris, cannas, calla lilies, ginger
  • Corm – crocus, gladiolas, bermuda grass
  • Tuber – dahlias, caladiums, begonias, potato

When selecting bulbs, corms, rhizomes or  tuberous roots, make sure there are no mushy parts.  They should feel firm and dry.