Some people burn candles the minute they get home while others build a small museum.
Candle hoarding usually comes from good reasons:
- Saving a scent for a specific season
- Keeping a limited run candle pristine
- Treating candles as décor
- Buying backups because you loved it
Here is the part most people do not realize:
Wax is not perfectly inert. Especially soy-based wax. Over time, its crystal structure can shift and fragrance can fade. That does not guarantee failure, but it does increase variability, particularly under fluctuating storage conditions.
Wax Polymorphism. Why Wax Can Change
Soy wax is made from hydrogenated soybean oil. Like other fat-based systems, it forms crystal networks. In these systems, the same molecules can pack into different crystal arrangements, a phenomenon called polymorphism. Those arrangements influence hardness and melting behavior.
We've seen this most clearly as frosting, the white crystalline bloom that appears on soy candles after temperature swings.
Why this matters for burning is simple: A candle works by melting wax into liquid fuel. The wick draws that fuel upward, where it vaporizes and burns. If the surface becomes slightly harder or more crystalline, the melt pool can form more slowly or spread less easily to the edges.
Wick size and burn habits are still the main drivers of performance. Aging and storage act more like multipliers.
Why Soy Is More Sensitive Than Some Other Waxes
Soy’s fat‑based crystal network makes it more reactive to environmental change, particularly because polymorphic transitions in hydrogenated soybean oil can be induced by temperature shifts during storage.
Paraffin wax behaves differently. It is a highly refined petroleum wax that is chemically more inert and structurally more stable over time. It does not form the same crystalline bloom as soy and is generally less sensitive to temperature swings, airflow, humidity, and light exposure.
No wax is morally superior, they just behave differently.
This is one reason many manufacturers blend waxes. A blended system can reduce frosting and help maintain more consistent burn behavior as a candle ages.
Our candles use a balanced wax blend designed to combine the aesthetics of soy with the structural stability of paraffin.
None of this means a soy candle suddenly fails after a certain date, it just means natural wax systems respond more noticeably to their environment.
Does Aging Cause Tunneling?
Tunneling has well-known primary causes:
- The candle is under-wicked
- The first burn was too short to establish a full melt pool
- Drafts disturb the flame
In most cases, tunneling is about wick setup or burn duration.
Anecdotally, some makers and users notice more tunneling complaints when candles have sat unused for long periods. The plausible mechanism is that a slightly harder or more crystallized surface may be less forgiving if the candle is already marginally wicked or burned in short sessions.
Aging does not create tunneling on its own. It can amplify existing weaknesses.
Before You Blame the Wax
Tunneling is often user behavior.
If you regularly burn a candle for 45 to 60 minutes and extinguish it before the melt pool reaches the edges, the candle may form a memory ring. Most container candles need 2 to 3 hours on early burns to establish a full melt pool, depending on diameter.
In many cases, the issue is simply burn duration, not wax chemistry.
Where aging may play a role is in edge cases. A candle that has developed a slightly firmer surface can be less forgiving if it is already being burned in short increments, the chemistry amplifies the habit.
Practical Storage Rules
If you are going to stash candles, aim for stability.
Best conditions:
- 60°F to 75°F
- Away from direct sunlight
- Away from vents and radiators
- Covered or boxed
Avoid:
- Garages and attics
- Window sills
- Places with frequent hot-cold cycling
Stable storage slows structural change and scent loss.
A Realistic Timeframe
Candles do not truly expire, but performance can drift.
- Within about 12 months. Most predictable burn and scent.
- 18 to 24 months. Usually fine, with higher odds scent fade or tunneling.
- Beyond that. Expect variability. Some will burn beautifully. Some may be stubborn.
Good storage extends these windows while temperature swings shorten them.
Signs a Candle Has Been Sitting
Look for:
- Slight pull-away from the vessel
- A firmer or glossier surface
- Weaker cold scent
- First burn struggling to form a wide melt pool
- An offensive amount of dust on the surface
These are not outright failures, but they are pointing to signs of structural and fragrance aging.
How to Rescue a Tunneling Candle
If a candle continually tunnels, you have options:
1. The foil method
Wrap foil loosely around the top, leaving an opening above the flame. The trapped heat helps melt the outer wax and level the surface.
2. Use a candle lamp
A top-down warmer can even out the surface when the wick struggles to do it alone.
3. Repurpose the wax
Turn it into melts or use a warmer to extract remaining fragrance.
Bottom Line. Burn the Good Stuff Sooner
Candles are designed to melt. Wax can shift a little over time, especially if it’s been sitting through a few seasons. Most of the time, that change is subtle. Sometimes it just means the candle is a little less forgiving than it would have been fresh.
Save a few if you want. Just don’t let every candle become “special occasion.” If there’s a visible layer of dust on the lid, that’s probably your cue.
Light the good one. It’s wax, not fine china.
