Hairy Bittercress – March Weed Of The Month

By Hillary Thompson, Super-Sod
Photographs by Hillary Thompson, Super-Sod

March's weed is Cardamine hirsuta (hairy bittercress), a common edible weed in the mustard family. You'll find it growing in wet, sparse lawns and wet soils in general.

Hairy bittercress is kinda cute. Can a weed be cute? Watch our Weed of the Month from our Lawn Tips Live recorded live at our Greenville, SC store to learn more so you can determine its cuteness for yourself. 

Hairy Bittercress ID Features:

• Grows in a basal rosette from one center point, with "branches" (really compound leaves) radiating to form 2 to 4" diameter clumps.

• Small, white flowers; small-but-noticeable because they're held above the foliage.

• The fruits are green tubular pods that mature to brown and are held upright above the foliage – a great architecture for seed dispersal (which can be up to 1,000/plant).

See more pictures on the NCSU Extension webpage for bittercress.

The photo at the top of the page shows you a 2" diameter, young bittercress snapped in February. This picture directly above shows you a 4" diameter, older plant captured in the wild this week. Please note how many tiny flowers and seed pods are on this plant. It's bursting with life!

This little cutie can go to seed even when very small (especially as day length increases), which is not cute behavior at all. There's probably a lot of this in your neighborhood as it loves disturbed soils. Below is the little white flower that puts it in the mustard family, the Brassica family. You can also see the brownish pod that will burst to send seeds flying.

Eat it or Treat it

Hairy bittercress is an annual weed in the mustard family. Can you believe it, another edible weed? Is this going to be a trend? The flavor is strong, like you'd expect out of a mustard relative. If you choose not to take a test nibble to see if you want to include it in your salad, then there are three paths for eradication.

Prevention: In September spread pre-emergent herbicide to prevent germination of winter weeds, such as hairy bittercress (same goes for weeds from previous tips: annual poa, chickweed). Come by for products!

It is easy to prevent with thick layers of mulch or by cultivating a thick, healthy lawn.

Manual: Hand pull bittercress – super fun and satisfying to hand weed. Much like annual poa, it's easy to yank up a clump and you get it all at once – so no worries about something sprouting back.

Mow to keep larger plants from going to seed, but remember it can flower when diminutive and below mowing height (this vexing behavior reinforces how pre-emergent prevention is the best form of weed control).