Of all the broadleaf weeds that show up in Minnesota lawns, creeping charlie and wild violet are in a category of their own. Homeowners spray them, they come back. They spray again, the patch gets smaller for a few weeks then rebounds. This isn't a product failure or an application error — it's a biological reality rooted in how these plants are built and how herbicides actually work. Understanding both is the key to treating them effectively instead of just repeatedly irritating them.
Anatomy — Why These Two Weeds Are Built to Survive
Creeping Charlie
Wild Violet
The Three Biological Defenses That Make Them Nearly Impossible to Kill with a Single Treatment
1. Waxy Leaf Cuticle — The Herbicide Barrier
Both creeping charlie and wild violet have a noticeably waxy leaf surface. This isn't cosmetic — it's a survival mechanism. The waxy cuticle is the first barrier herbicide has to penetrate to enter the plant's vascular system. On a standard broadleaf weed like dandelion, herbicide droplets absorb into the leaf surface readily. On wild violet especially, herbicide droplets bead up and roll off, never entering the plant at meaningful rates.
This is why wild violet in particular develops a reputation for being "immune" to weed killer. It isn't immune — the product just isn't getting in. This is also why products specifically formulated for violets and ground ivy include surfactants or penetrants in their chemistry, and why application during active transpiration (when the plant is actively pulling water and nutrients) dramatically improves uptake.
2. Distributed Root Systems and Stolon Networks (Creeping Charlie)
Dandelions have a single taproot. Kill the top growth and damage the taproot sufficiently, and the plant dies. Creeping charlie has no taproot. It has a network of stolons — horizontal stems running across the soil surface and through the thatch — rooting at every node. A single square foot of mature creeping charlie may have 15–25 separate rooting points.
When you treat creeping charlie and kill the visible top growth, you haven't necessarily killed those rooting nodes. Any node that didn't receive a lethal herbicide dose regrows. This is why partial creeping charlie control — the patch shrinks but never dies — is so common. Enough herbicide reached some nodes, not enough reached others.
3. Deep Rhizome Energy Storage (Wild Violet)
Wild violet's rhizome is a fleshy underground energy storage organ — functionally similar to a potato. Even when a systemic herbicide kills every leaf blade visible above ground, the rhizome sitting 3–6 inches below the soil surface holds enough stored carbohydrate energy to regenerate the plant from scratch. This is why wild violet often comes back seemingly untouched 3–4 weeks after what looked like a successful kill.
The only way to truly eliminate wild violet is to get a lethal dose of systemic herbicide translocated into the rhizome itself. Which brings us to the most important factor in treating these weeds effectively — timing.
Wild violet's hidden weapon — cleistogamous seeds:
Wild violet produces two kinds of flowers. The visible purple spring flowers everyone recognizes. And cleistogamous flowers — self-fertilizing flowers produced underground at soil level throughout summer, invisible from above, that generate seed without ever opening. This means wild violet is actively reseeding itself even when you see no above-ground flowers. A single violet plant can produce hundreds of seeds annually through this mechanism — which is why populations don't just persist, they expand even after visible top growth is controlled.
Translocation — The Science Behind Why Timing Changes Everything
Systemic herbicides — the class that includes triclopyr, dicamba, and the three-way broadleaf products effective against these weeds — work by being absorbed through leaf tissue and transported through the plant's vascular system to the roots and rhizomes. This movement through the plant is called translocation, and it is not constant throughout the season. It follows the plant's own carbohydrate movement patterns — and understanding those patterns is what separates one effective treatment from three ineffective ones.
How Herbicide Translocation Works in Creeping Charlie & Wild Violet
⬇ Downward Translocation — Best Treatment Window
As days shorten and temps cool, both weeds begin moving carbohydrates and sugars downward — from leaves to roots and rhizomes for winter storage. Systemic herbicide applied to the leaves rides this downward carbohydrate flow directly into the root system and rhizome. This is the most effective treatment timing because the herbicide reaches and kills the storage organ — the part of the plant that survives winter and regrows in spring.
⬆ Upward Translocation — Strong Second Window
As the plant breaks dormancy, carbohydrates and energy move upward from roots to fuel new leaf growth. Systemic herbicide applied during active spring flush moves upward with this flow and reaches actively growing tissue throughout the plant. Treat when plants are in full leaf expansion — 3–4 weeks after emergence. This window closes as temps rise above 85°F and translocation slows.
Why Summer Treatments Consistently Underperform
During the peak of Minnesota's summer — July and August — translocation in both creeping charlie and wild violet slows significantly. The plant isn't actively moving carbohydrates up or down; it's in a maintenance phase conserving moisture and energy during heat. Herbicide applied to leaves during this window is more likely to stay in the leaf tissue, cause localized damage, and fail to reach the roots and rhizome in sufficient concentrations to kill them. The result is the same pattern homeowners describe repeatedly — the weed looks dead for two weeks then bounces back fully from the undamaged root system.
The Minnesota Treatment Calendar
The fall window is the most important treatment of the year for both weeds:
For creeping charlie and wild violet specifically, a well-timed fall application in September will consistently outperform 2–3 summer treatments. The downward carbohydrate flow moves herbicide into the very tissue — roots, rhizomes, stolon nodes — that allow these plants to survive winter and regrow. Kill the storage organ in fall and the plant has nothing to draw from in spring.
In Owatonna, Austin, and Rochester MN, target the September 1 through October 10 window. Apply on a calm day when temps are between 55–80°F, the plant is not drought-stressed, and rain is not expected for 24–48 hours after application.
Product Selection — Not All Broadleaf Herbicides Work
This is where many homeowners make a costly mistake. Standard 2,4-D alone does not control creeping charlie or wild violet reliably. Both weeds have demonstrated significant resistance or reduced sensitivity to 2,4-D as a standalone active ingredient. Effective control requires products that include triclopyr or dicamba — either as standalone actives or in three-way combination formulas.
- Triclopyr — most effective single active for creeping charlie and violet. Requires a labeled product specifically mentioning ground ivy and/or violet control.
- Three-way broadleaf herbicides (2,4-D + MCPP + dicamba) — effective combination when all three actives are present at proper rates. Commonly available and labeled for both weeds.
- Avoid annual ryegrass-type products or straight 2,4-D — insufficient control of either weed at typical use rates.
Always read the label and confirm creeping charlie (Glechoma hederacea or "ground ivy") and/or wild violet (Viola spp.) are listed as controlled weeds. Products not specifically labeled for these weeds will likely provide incomplete control regardless of timing.
Multi-Year Commitment — The Reality
Even with perfect timing, product selection, and application technique, heavily established creeping charlie and wild violet infestations rarely die in a single treatment cycle. Expect a 2–3 year program of properly timed fall and spring applications to achieve full control. Here's what realistic progress looks like:
- Year 1 (fall + following spring): 50–70% reduction in visible coverage. Some regrowth from surviving nodes and rhizomes.
- Year 2 (fall + following spring): 80–90% reduction. Isolated patches persisting in areas with dense shade or missed coverage.
- Year 3: Near-complete control with spot treatments on surviving patches.
Filling the turf density simultaneously with a fertilization program that thickens the lawn is essential — thin, shaded turf is what gave these weeds their foothold in the first place. A dense Kentucky Bluegrass canopy physically prevents creeping charlie from establishing new stolon contact and blocks the light germinating violet seeds need.
Creeping charlie or wild violet taking over your lawn?
PeakGreen's weed control programs target both with properly timed spring and fall applications across Owatonna, Austin, Rochester, and all of southern Minnesota. Call for a free estimate.
Call 507-440-7823