Every spring, without fail, I get a version of this call.
“Bob, we installed landscape lighting last year… and it already looks faded.”
Not completely dead. Not totally dark.
Just dimmer. Uneven. Not as sharp or dramatic as it looked the night it was installed.
Sometimes the homeowner adds:
“They told us LED lasts forever.”
And here’s where I slow the conversation down.
After 42 years designing, installing, repairing, and rebuilding outdoor lighting systems across Maryland, Northern Virginia, and Washington, DC — from Rockville and Bethesda to Columbia, Annapolis, Fairfax, Arlington, McLean, and Potomac — I can tell you this clearly:
LED technology lasts a long time.
But LED landscape lighting systems don’t fade because of the diode.
They fade because of everything around it.
In the DMV, our climate exposes shortcuts quickly.
Let me walk you through what’s really happening when LED landscape lights lose brightness after one season — and how to fix it the right way.
Because this isn’t about bulbs.
It’s about system design.
First: LED Doesn’t Mean Maintenance-Free
There’s a common misunderstanding that once you install LED landscape lighting, you’re done for 15–20 years.
The diode itself may last that long.
But your lighting system also includes:
- A transformer
• Underground wiring
• Waterproof connections
• Seals and gaskets
• Fixture housings
• Mounting hardware
• Photocells or timers
In Maryland’s environment — humid summers, clay soil, freeze–thaw winters, heavy pollen, and irrigation overspray — those components take a beating.
When something starts to look “faded,” it’s usually a system imbalance, not a burned-out LED.
The #1 Reason Lights Look Dim After One Season: Voltage Drop
This is the most common issue we correct.
In many builder-grade or budget installs, the wire gauge is undersized for the distance it runs.
Here’s what that means in plain English.
The transformer sends 12 volts down the line.
But electricity loses strength over distance.
If the wire is too small, by the time power reaches the last fixture, it may only be receiving 9–10 volts.
LED fixtures are extremely sensitive to voltage consistency.
When voltage drops:
- Brightness decreases
• Color temperature shifts
• Light output becomes uneven
• Fixtures flicker
• Drivers degrade faster
In a Rockville backyard we corrected last year, the homeowner thought all their fixtures were failing.
We tested voltage.
There was nearly a 3-volt drop at the end of the line.
The LEDs weren’t bad.
The wire sizing was.
We rewired key runs and rebalanced the load.
Instant brightness improvement.
The #2 Issue: Cheap Fixture Housings
Not all LED fixtures are created equal.
Lower-cost fixtures often use:
- Thin aluminum bodies
• Minimal heat management
• Low-grade internal drivers
• Weak seals
Maryland humidity gets inside those fixtures.
Moisture intrusion causes:
- Internal corrosion
• Clouded lenses
• Reduced light output
• Premature driver failure
In Annapolis and Severna Park especially, where moisture levels stay high near the Bay, I see corrosion faster than homeowners expect.
Quality brass or composite fixtures cost more upfront.
But they don’t degrade after one season.
The #3 Problem: Dirty Lenses and Mineral Build-Up
This one surprises people.
After a full Maryland season, fixtures collect:
- Pollen
• Mulch dust
• Dirt splash
• Spider webs
• Irrigation overspray residue
Even a thin film over the lens reduces brightness noticeably.
In Columbia, I walked a property where the homeowner thought their system was failing.
We cleaned the lenses.
Brightness improved dramatically.
Landscape lighting needs annual maintenance — especially in our climate.
The #4 Culprit: Irrigation Overspray
This is one of the biggest hidden problems in the DMV.
Sprinkler heads that spray directly onto lighting fixtures cause:
- Mineral deposits
• Hard water stains
• Corrosion at wire connections
• Lens clouding
In clay soil areas like Montgomery County, irrigation often runs longer.
If water hits fixtures repeatedly, they degrade quickly.
Lighting and irrigation must be designed together.
If they aren’t coordinated, one system slowly damages the other.
The #5 Problem: Undersized Transformers
I see this often when homeowners expand systems over time.
They add:
- A few path lights
• A couple tree uplights
• Maybe deck lighting
But the original transformer wasn’t sized for growth.
When wattage approaches or exceeds capacity, output drops.
The system looks tired.
Transformer upgrades typically range:
$800–$2,000 installed in the DMV.
But proper sizing restores balance immediately.
A Bethesda Case Study
A homeowner in Bethesda called because their backyard lighting “just didn’t pop anymore.”
Installed 14 months earlier by another contractor.
We found:
- Undersized wire
• Transformer running at near max capacity
• Multiple taped splices (not waterproof connectors)
• Irrigation overspray on several fixtures
We:
- Upgraded transformer capacity
• Rewired longest runs
• Rebuilt connections properly
• Re-aimed irrigation heads
• Cleaned and resealed fixtures
Total corrective cost: about $4,800.
Full system replacement would have exceeded $12,000.
The LEDs weren’t the issue.
The installation strategy was.
Environmental Stress in Maryland
Our region is hard on outdoor infrastructure.
We deal with:
- High summer humidity
• Heavy pollen seasons
• Clay soil movement
• Freeze–thaw cycles
• Rapid temperature swings
Low-quality materials installed without voltage planning rarely last here.
The climate exposes shortcuts quickly.
What Proper Installation Should Include
If you want LED lighting that still looks strong five years from now, installation should include:
- Correct wire gauge for run length
• Transformer sized with 20–30% expansion margin
• Waterproof gel-filled connectors
• Proper burial depth (at least 6 inches for low-voltage wire)
• Pressure-regulated irrigation nearby
• Quality brass or commercial-grade composite fixtures
• Annual inspection and cleaning
Lighting is infrastructure.
Not decoration.
What It Costs to Correct Fading Systems
In the DMV, corrective costs typically range:
Cleaning and maintenance:
$200–$600
Transformer upgrade:
$800–$2,000
Voltage balancing and rewiring sections:
$1,500–$4,000
Selective fixture replacement:
$2,000–$6,000
Full system replacement:
$8,000–$18,000+
Diagnosis determines scope.
Most fading systems do not require full replacement.
They require proper engineering correction.
The Bigger Lesson
When LED landscape lights fade after one season, it’s rarely because the LED “burned out.”
It’s usually because:
- Voltage wasn’t managed correctly
• Materials weren’t designed for Maryland’s climate
• Installation shortcuts were taken
• Maintenance was ignored
After 42 years serving Maryland and Northern Virginia homeowners, I’ve learned this clearly:
Outdoor lighting systems either age gracefully — or they expose weaknesses quickly.
And graceful aging starts with proper design.
The Bottom Line
If your LED landscape lights look faded after one season, don’t assume the bulbs are defective.
Look at the system.
Check:
- Voltage drop
• Transformer capacity
• Fixture quality
• Irrigation overspray
• Moisture intrusion
• Connection integrity
In the DMV, lighting systems need margin built into them.
Because our environment will test every weak point.
When lighting is engineered properly, it doesn’t just look good the first night.
It holds up.
Quietly.
Season after season.