Tubers, Corms, Rhizomes, and Bulbs... What's the Difference?

Over time, the term "bulb" in gardening terminology has come to describe any type of root form that is planted in the ground to produce a plant. However, only a few of these plants can truly be defined as bulbs. There are four different types of reproductive structures, including Tubers, Corms, Rhizomes, and Bulbs. We'll explain exactly what the true difference is between these four terms!

Dahlia TuberDahlia Tuber
Dahlia Tuber
Saffron CrocusSaffron Crocus
Saffron Crocus Corms
bearded iris rhizomebearded iris rhizome
Bearded Iris Rhizome
Tulip BulbsTulip Bulbs
Tulip Bulbs

Tuber

Tubers are formed from a stem or root. They store nutrients that allow the plant to grow the following season. Shoots grow upwards from many different places on the tuber. Examples of tubers are Dahlias, Begonias, Anemones and Potatoes. 

Corm

Corms are actually enlarged underground stems that store nutrients, surrounded by papery outer layers. After stems sprout from the corm, buds form on top of the stem. Corms at their center are solid tissue, whereas Bulbs are immature layers of leaves. At the end of the growing season, a new corm typically grows on the base of the spent one, and plants regrow from new corms each season. Examples of corms are Gladiolus and Crocus.

Rhizome

Rhizomes are stem-like structures that grow horizontally across the ground, forming roots from the bottom while sending shoots upward. Buds form at different parts along the structure, not necessarily at the top. Rhizomes store nutrients for newly growing plants. Examples of rhizomes are Bearded IrisCanna Lilies, and Calla Lilies.

Bulb

A bulb is comprised of a plant's stem and leaves. The bottom of the bulb is a compacted stem, and roots grow from this part of the bulb. Layers of nutrient-filled leaves sit at the bottom of the bulb and surround a bud that eventually becomes the flower. Examples of bulbs are Tulips, Lilies, and Daffodils.

 

Whether your plants are growing from a Tuber, Corm, Rhizome, or Bulb, all of these plant structures are sure to produce a spectacular show in the spring and summer months. Happy Gardening!

If you have questions about how to grow these plants, visit The Tool Shed, our source for helpful planting guides! Or, contact us to speak to our team for friendly garden advice.

Shop Flower Bulbs (and Corms, Rhizomes, and Tubers!)

  1. 'Barrett Browning' Small Cupped Daffodil, Narcissus 'Barrett Browning'

    The Barrett Browning Small Cupped Daffodil is named for poet Elizabeth Barret Browning, who penned the famous line “How do I love thee? Let me count the ways.” True to it...

    Learn More
    Barrett Browning Small Cupped Daffodil Small Cupped Daffodil Narcissus 'Barrett Browning'
    As low as $11.99 Sale $8.99
    Per Bag of 8
    The Barrett Browning Small Cupped Daffodil is named for poet Elizabeth Barret Browning, who penned the famous line “How do I love thee? Let me count the ways.” True to its namesake, this cultivar has been a beloved favorite since its introduction in 1945. Blooming in mid-spring, it is an early season delight with broad, crisp white petals contrast a frilled tangerine-orange cup. Winner of the Wister Award for outstanding garden daffodils from the American Daffodil Society. (Narcissus)
  2. Red Hunter Tulip or Wisley Tulip, Tulipa linifolia (Batalinii Group) 'Red Hunter'

    Red Hunter Tulip, also called Wisley Tulip, features brilliant red flowers around a black center. Starting Tulip season with a pop of color and blooming longer than most species tuli...

    Learn More
    Red Hunter Tulip Red Hunter Tulip or Wisley Tulip Tulipa linifolia (Batalinii Group) 'Red Hunter'
    As low as $13.99 Sale $10.49
    Per Bag of 15
    Red Hunter Tulip, also called Wisley Tulip, features brilliant red flowers around a black center. Starting Tulip season with a pop of color and blooming longer than most species tulips, its mid-to-late spring flowers are surrounded by narrow, upright, silver-green leaves. Plant at the front of the garden or in containers, where the scarlet flowers and attractive foliage will catch your eye. Winner of the RHS Award of Garden of Merit. (Tulipa linifolia Batalinii Group)
  3. Woodstock Hyacinth, Hyacinthus orientalis 'Woodstock'

    With deep plum blooms with a rich fragrance, Woodstock Hyacinth is a gorgeous addition to the spring garden. The warm purple blossoms will complement bright yellow daffodils and pair...

    Learn More
    Woodstock Hyacinth Woodstock Hyacinth Hyacinthus orientalis 'Woodstock'
    As low as $11.99 Sale $8.99
    Per Bag of 6
    With deep plum blooms with a rich fragrance, Woodstock Hyacinth is a gorgeous addition to the spring garden. The warm purple blossoms will complement bright yellow daffodils and pair nicely with jewel-toned tulips. Early-to-mid-spring blooms are known for attracting bees with plentiful nectar. Plant in the front of the garden or in containers to enjoy the sight and scent of Woodstock Hyacinth. (Hyacinth orientalis)
  4. Wild Woodland Tulip, Wild Tulip, or Florentine Tulip, Tulipa sylvestris

    Wild Woodland Tulip is an heirloom Wildflower Tulip, or Botanical Tulip, that has been cultivated for hundreds of years. With luminous yellow flowers atop burgundy stems, this tulip ...

    Learn More
    Wild Woodland Tulip Woodland Tulip, Wild Tulip, or Florentine Tulip Tulipa sylvestris
    As low as $11.99 Sale $8.99
    Per Bag of 15
    Wild Woodland Tulip is an heirloom Wildflower Tulip, or Botanical Tulip, that has been cultivated for hundreds of years. With luminous yellow flowers atop burgundy stems, this tulip will light up the mid to late spring garden and delight with a sweet lemony fragrance. Vigorous, long-lived, and relatively tall for a Species Tulip, Wild Woodland Tulips are a great choice for naturalizing in grassy areas. (Tulipa sylvestris)
© 2022 AmericanMeadows.com All rights reserved