Controlling Cockleburs in a Wildflower Meadow Without Harming Bluebonnets

Controlling Cockleburs in a Wildflower Meadow Without Harming Bluebonnets

A San Antonio (zone 8) gardener has native prairie grasses and bluebonnets mixed with cockleburs (spiny burs). They want a herbicide that kills cockleburs but spares wildflowers.

Herbicide Caution

No selective herbicide distinguishes cockleburs from broadleaf wildflowers like bluebonnets. Both are broadleaves.

Alternative Strategies

• Spot-treat: Carefully apply a non-selective herbicide (e.g., glyphosate) to cocklebur rosettes with a shielded sprayer or wiper before they bolt.
• New product: Spectracide "3-Strikes" (battery sprayer) may allow precise application.
• Mowing: Mow cockleburs before burs form; repeat as needed.
• Hand-pull: For small areas, pull when soil is moist.

Grass Planting

Planting more grass (e.g., blue fescue) won't choke wildflowers if chosen carefully, but won't eliminate established cockleburs.

Early spring action is critical—cockleburs are annuals; prevent seed set.