Redstem filaree, courtesy of Joe Dixon
Have you ever been out in your yard and come across a plant that strikes you as pretty, but you don’t remember planting it? The thought may cross your mind, “Is this a weed or a wildflower?” In other words, “Should I be nurturing this plant or killing it?”
One such plant you may have encountered recently is a dainty little groundcover with cute little purple flowers. If you look closely, you’ll notice each flower has five petals.
Measuring only 2-5 inches tall, the leaves are hairy and finely divided, like a fern or carrot. After the flowers fade, you’ll notice each flower develops five fruits, each with an elongated tail. If you use your imagination, the fruits look somewhat like a stork’s bill.
You may find it mixed in with other groundcovers, sprouting in pea gravel mulch, colonizing bare spots in thin lawns, and growing in areas where wood mulch has gotten too thin. It looks similar to woolly thyme or a miniature geranium.
So is it a weed or a wildflower?
And the answer is (drumroll please)…WEED. This plant is redstem filaree (Erodium cicutarium). Originally from the Mediterranean, Spanish explorers reportedly introduced to California in the 1700’s. Click here to see close up photos.
Even though it’s a very pretty little plant, it can take over your lawn or garden if you ignore it. It can also harbor plant diseases that can infect your vegetable garden. It’s a good idea to get rid of it before it produces seeds and the problem gets worse.
How should you control it?
The best option is to weed it. If you get the crown and part of the root, it won’t come back. It doesn’t regrow from the pieces of root left in the ground. Nonetheless, weeding redstem filaree can become tedious if you’re not much of a detail-oriented person. This is a good time to tuck your iPod in your pocket and take the time to tackle it.
Redstem filaree seed germinates in the fall just like downy brome. It overwinters as a little plant, then flowers and produces seed in spring. After the seeds mature, the individual plants die. If you can remove it before the seeds fall from the plants, you will have made a good dent in the problem.
Preventing More Plants
After you finish pulling it, topdress your wood or bark mulch so it’s at the recommended depth. A 3-4 inch mulch layer will prevent new seed from germinating. This approach can reduce the problem pretty effectively.
If you have a recurring problem with it in rock mulch, try applying weed preventer in late August or September to keep the new seeds from growing into weeds.
A Great Alternative
If you’re secretly wishing you had a nice groundcover like redstem filaree and feel a pang of sadness about pulling it, you might want to consider a creeping veronica instead. I’m a big fan of Crystal River veronica, because of its beautiful blue flowers in May, deep green leaves, drought tolerance, and vigorous growth habit. It’s a nice plant to tuck in between flagstone pathways.
Special thanks to Joe Dixon for asking a great question and sharing his photo.
Catherine, how about spraying with broadleaf weed killer (2-4-D)? Or does that kill the plant and leave the seeds?
Hi Joe, according to Colorado State University, 2,4-D is only marginally effective on redstem filaree. The other problem with spraying them at this time of year is that most herbicides don’t work that well when the plant is in flower or about to produce seeds. Weed killers are much more effective when the weed is smaller (younger) and actively growing. An herbicide might work better on redstem filaree in the late fall or early spring. That being said, how about you give it a try on a few plants and let us know the results?