Plants Without Borders – The Rhizomatous

April 29, 2026

A snowberry purchase

Did you buy plants at our recent plant sale? If so, thank you very much for your support! In case you are new to the growing habits of certain native plants, I will share what I recently learned about reproductive advantages of certain plants.

Himalayan blackberry (Rubus armeniacus), an especially invasive plant in our temperate climate, is not a native plant, but it’s a good example of how certain species can get completely out of control.

H. blackberry is a powerful reproducer. It can reproduce by seed, both near and far, with the help of birds and other animals. But it also has other tricks up its sleeve. When canes grow long they touchdown and take root. Voilà! A new plant. But the real magic of H. blackberry is its ability to create a new plant from a small piece of above-ground stem containing just one node, or a piece of underground horizontal stem (rhizome). Oops ! The blackberry lives on! And, a non-native plant out of it’s homeland (Armenia and northern Iran) does not have the climate, pathogen, or herbivore pressure that it would have back where it came from.

I don’t know of any native plant with that degree of aggressiveness but let’s pondera few of our native plants that might stretch a bit further than what you had in mind. Some native plants spread more easily than others.

Great camas

If a plant relies on seed dispersal for survival, you have a chance to do something about it; deadhead the plants before the seeds are viable.* Great camas (camassia leichtlinii) seeds readily. The photo shows the multitude of small offspring near the ground.

Snowberry (symphoricarpos albus) can spread rapidly via suckering (or root sprouts). Suckers are shoots that grow from adventitious buds on its roots, often some distance from the base of the shrub. So, keep it pruned.

Plants can push out new plants via runners. Our Woodland strawberry (fragaria vesca) runner will have nodes along its length which can take root. These runners are visible and you can clip them.

Oregon State Univ.

Plants that reproduce by spores, like Western sword fern (polystichum munitum), reproduce new individual plants that you can certainly pull out, if unwanted.

Now we bring up the daunting method of reproduction – reproduction by rhizome. A rhizome is an underground, modified stem arising from an adventitious bud in the root crown zone. (See drawing) Underground reproductive systems like rhizomes can make plant removal difficult because little pieces of the rhizomes are left behind, leaving a new clump of growth ready to surface. Rhizomes are also protected from trampling, and serve as storage tissue for vegetative propagation. All of these features allow these

Western lily of the valley

plants to burst their britches. Note the photos of rhizomatous native plants that have taken over a larger territory than intended. Western Lily of the Valley (maianthemum dilatatum)

W. starflower

digging under the fence into the neighbors yard, Western starflower (lysmachia latifolia) bleeding into the grass, and Inside-out flower (vancouveria hexandra) tunneling under netting. But lovely plants all!

Inside-out flower

Still, there are solutions. You can weed back the edge of your fast-spreading plant clump or plant within concrete borders. You can also plant a ‘spreader’ in a pot, like many people do with spreaders like mint or oregano.

Not all rhizomatous plants spread aggressively. Wild ginger (asarum caudatum), Douglas’ aster (symphyotrichum subspicatum), and Hooker’s Fairybells (Prosartes hookeri var. oregana) spread by rhizomes but they are more shy.

In conclusion, be on the lookout when plants spread by underground structures! Now you see em, now you see more!

Ruth

*I was taught, for many seeds, if you can’t make a dent into the seed with your finger nail then it’s likely viable.

References:

Pacific Northwest Native Groundcover Plants
Dana Kelley Bressette, 2023
Chart includes how the plants spread

Click to access Native-Groundcovers.pdf

Real Gardens Grow Natives
Eileen M. Stark, 2014, ‎ Skipstone Publishing

Bullying blackberries by Adriana Janovich
Summer 2021, Washington State University Magazine
https://magazine.wsu.edu/web-extra/bullying-blackberries/#:~:text=He%20also%20sold%20seeds%20from,consumers%20in%20a%20special%20circular

Garden gone awry? How to Control Aggressive Garden Plants
Candice Anderson, July 25, 2017, Univ. of Ill. blog.
https://extension.illinois.edu/blogs/know-how-know-more/2017-07-25-garden-gone-awry-how-control-aggressive-garden-plants

Nursery Manual for Native Plants
A Guide for Tribal Nurseries
R. Kasten Dumroese, Tara Luna and Thomas D. Landis, editors
p. 153-175, Luna, Tara. 2009. 9: Vegetative propagation. In: Dumroese, R. Kasten; Luna, Tara; Landis,
Thomas D., editors. Nursery manual for native plants: A guide for tribal nurseries –
Volume 1: Nursery management. Agriculture Handbook 730. Washington, D.C.: U.S. Department of
Agriculture, Forest Service.

Click to access wo_AgricHandbook727_153_175.pdf

UF/IFAS Extension blog
How Plants Make More Plants (and How You Can Too)
Julia Sirchia, 2026
https://blogs.ifas.ufl.edu/pascoco/2026/03/17/how-plants-make-more-plants-and-how-you-can-too/