If you garden in a climate with freezing winters, you've probably experienced this moment: Spring arrives, the snow melts, and garden edging that once looked straight and settled now appears lifted, shifted, or out of alignment.
It's natural to blame "a rough winter," and that instinct isn't wrong. But edging rarely moves because of a single cold season or a single event. Instead, freeze-thaw cycles act as a repeating stress on soil, gradually changing how the ground supports and restrains edging over time.
This article focuses on how freeze-thaw works, why it affects garden edging the way it does, and why the results often become visible only after years of seasonal change - not all at once.
The Two Seasonal Forces - Freeze-Thaw - at Work
Freeze-thaw affects soil in two primary ways. One is easy to recognize. The other is more subtle, but just as important.
Force #1 - Frost Heave and Vertical Lift
A well-documented physical process called frost heave explains why objects in the ground can be pushed upward during winter.
When water in soil freezes, it doesn't simply expand in place. Under the right conditions, it forms ice lenses below the surface.
"Ice lenses are bodies of ice that form when moisture diffused within soil accumulates in localized zones; as these lenses grow, they wedge the soil apart and play a key role in frost-induced heaving of soils."
"Ice Lenses." In ScienceDirect Topics: Frost Heave. Elsevier.
These ice layers grow as additional water migrates toward the freezing front, and as they expand, they exert upward pressure on the soil above them.
As ice lenses form, soil is lifted where resistance is lowest.
"Frost heave is the upward displacement of the ground surface caused by the formation and growth of ice lenses within frost-susceptible soils."
"Frost Heave." ScienceDirect Topics - Agricultural and Biological Sciences, n.d.
When temperatures rise and the soil thaws, the ice disappears - but the soil does not always settle back into its original position or density. This naturally displaced soil is why edging, pavers, and borders can shift into a higher position in Spring than they were in Fall.
This vertical movement is one of the most visible effects of freeze-thaw, and it's often the first sign that seasonal soil forces are at work.
Force #2 - Seasonal Thaw and Soil Shift
Freeze-thaw doesn't just move soil vertically. Over time, it also changes soil structure.
Repeated freezing and thawing creates small separations between soil particles. As ice forms and melts, particle contacts are disrupted, micro-voids develop, and the soil becomes less densely packed. In practical terms, this means the soil loses some of its ability to hold embedded objects firmly in place.
"Freeze-thaw action results in particle fragmentation, increased soil porosity, and elevated crack content, thereby contributing to soil structure deterioration and strength reduction."
Zhang, S., et al. "Effects of Freeze-Thaw Cycles on the Mechanical Properties of Soil." Applied Sciences, 2023.
As this weakened soil settles and resettles after each thaw, its holding power decreases. Root growth, foot traffic along garden paths, lawn equipment passing nearby - over time, these small, uneven forces allow edging to resettle slightly differently from season to season.
The movement is rarely dramatic. But across multiple years, these micro-adjustments accumulate, and edging can gradually drift sideways even when it never appeared to "pop up" in any obvious way.
How These Forces Show Up in the Garden
The important thing to understand is that freeze-thaw doesn't act once; it acts repeatedly.
Each winter contributes small changes to soil structure and alignment. Most of the time, those changes are subtle enough to go unnoticed. Eventually, a season arrives where the accumulated effects exceed what the system can visually hide - and that's when misalignment becomes obvious.
This is why gardeners often observe:
- edging lifting slightly above surrounding surfaces;
- long, straight runs of edging drifting out of alignment;
- corners opening or falling out of square;
- joints that were once tight loosening.
These are not separate problems. They are common consequences of the same seasonal forces acting over time.
Many installation guides focus on techniques intended to reduce freeze-thaw effects - deeper trenches, added drainage, tighter compaction, or heavier anchoring. These steps can influence how movement shows up, but they don’t eliminate the underlying seasonal forces described here.
Freeze/thaw still acts on soil year after year, which is why alignment issues can appear even in carefully installed systems.
Frequently Asked Questions
Does freeze-thaw really cause garden edging to move?
Yes. Freeze-thaw cycles actively change soil structure and density. Over time, this alters how well soil supports and restrains edging, which can lead to vertical lift, lateral drift, or both.
Why does edging move after winter even if it seemed fine before?
Because freeze-thaw effects accumulate. Soil can tolerate small changes for years before misalignment becomes visible. When it does show up, it often looks sudden even though the underlying changes have been happening gradually.
Is frost heave the only reason edging shifts?
No. Frost heave explains vertical movement, but soil weakening after thaw explains why edging can also drift sideways. Most real-world edging movement involves a combination of both effects.
Why does edging sometimes move sideways instead of just lifting?
After thaw, gravity helps soil settle downward again, but lateral confinement does not fully recover. Once soil loses density and strength, small everyday forces can gradually reposition edging sideways over multiple seasons.
Does deeper anchoring prevent freeze-thaw movement?
Depth can help resist some forms of movement, but it does not eliminate freeze-thaw effects. Seasonal soil change still occurs above and around anchors, which is why different anchoring methods behave differently over time.
Can any edging completely avoid freeze-thaw movement?
In freeze-thaw climates, no edging system is immune to seasonal soil change. The goal is not to eliminate movement entirely, but to manage how movement is expressed and how easily alignment can be maintained over time.
Can proper installation prevent freeze-thaw movement?
Careful installation can influence how freeze-thaw effects appear, but it doesn’t remove the underlying seasonal forces. Depth, drainage, and anchoring all matter — however, soil still expands, settles, and changes structure over time. That’s why even well-installed edging can require adjustment after multiple winters.
Next Steps
Learn more about what you're seeing
For a deeper look at how these symptoms develop - and how to recognize them early - see Why Does My Wood Garden Edging Keep Moving? (Common Causes & How to Spot Them).
Learn about what actually holds edging in place
If you’re deciding how to secure edging - or want to understand how different anchoring approaches respond once movement begins - see 2x Lumber Garden Edging: What Holds It in Place (and What Doesn't).
Plan a New Installation
If you're planning a new installation and want to account for seasonal soil movement from the start - see How to Install Landscape & Garden Edging That Stays Put.
References
U.S. Department of Agriculture, Agricultural Research Service. "Soil Freezing and Thawing Effects on Soil Physical Properties." USDA ARS, n.d. https://www.ars.usda.gov/research/publications/publication/?seqNo115=296485
"Ice Lenses." In ScienceDirect Topics: Frost Heave. Elsevier. https://www.sciencedirect.com/topics/earth-and-planetary-sciences/frost-heave
Hong, Y., Lu, M., Zhang, L. "Effects of Freezing and Thawing on Soil Shear Strength in Loessial, Sierozem, and Chernozem Soils." PMC, 2025. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12222726/
Naqvi, Wasif M., et al. "Investigating the Mechanism of Frost Heave in Soils." National Science Foundation-supported research, n.d. https://par.nsf.gov/servlets/purl/10341341
Zheng, Xiaoyan, et al. "Effects of Freeze-Thaw Cycles on the Shear Strength and Microstructure of Soil." Coatings, MDPI, 2024. https://www.mdpi.com/2079-6412/14/12/1577
Zhang, Tao, et al. "Effects of Freeze-Thaw Cycles on Soil Pore Structure and Mechanical Properties." Soil & Tillage Research, Elsevier, 2020. https://www.sciencedirect.com/science/article/pii/S0167198720305924
Hong, Yifan, et al. "Experimental Study on the Mechanical Properties of Soil Subjected to Freeze-Thaw Cycles." Advances in Civil Engineering, 2023. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12222726/