Selective Weed Control in Vinca Groundcover

A gardener recalls a professional spraying a vinca-covered hillside, killing grass, weeds, and morning glory but leaving vinca unharmed. They want to know the product.

Likely a Selective Herbicide

Professionals use products like Fluazifop-P-butyl (grass-specific) or 2,4-D + dicamba blends that spare certain broadleaf groundcovers. However, exact identification is impossible without the applicator's records.

DIY Alternative: Preen (Pre-emergent)

Preen (trifluralin or corn gluten) prevents seed germination without harming established plants. Apply in early spring and midsummer after removing existing weeds.

Caution

• Preen does not kill existing weeds—only prevents new ones.
• Do not use where you plan to sow seeds.
• Always read labels; some formulations harm certain groundcovers.

For post-emergent selective control, consult a licensed applicator or your local Extension office.