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LED vs HPS Grow Lights Compared
Compared

LED vs HPS Grow Lights Compared

The most important upgrade in indoor growing in 20 years — and the comparison most growers get wrong.

Why this matters

Quality full-spectrum LEDs now produce yields equal to or better than HPS at the same wattage, with far less heat. But HPS still has a real role for budget growers and certain stages.

Understanding the tradeoffs helps you spend smart instead of chasing trends.

What to look for

Efficiency

Top LEDs hit 2.7+ µmol/J of usable light. HPS tops out around 1.7 µmol/J. LED wins clearly on energy efficiency.

Heat

LEDs run cool enough to mount close to the canopy. HPS demands serious ventilation to manage heat.

Spectrum

Modern LEDs offer full or tunable spectra. HPS is yellow-heavy and unchanging.

Up-front cost

Equivalent-output LEDs cost 2-3x more than HPS up front.

Operating cost

LEDs use 30-50% less electricity, recouping the price difference over 1-2 grow cycles.

Lifespan

LED diodes last 50,000+ hours. HPS bulbs need replacing every 12-18 months of regular use.

Budget, mid range or premium?

Here is what each level actually buys you.

Budget

Budget HPS kit

$120 – $250

400W or 600W HPS bulb, ballast, hood and basic timer.

Best for

Tight budgets where up-front cost matters more than long-term savings.

Mid range

Mid-range LED

$200 – $450

100-240W quantum board LED with Samsung or Bridgelux diodes.

Best for

Most home growers — efficient, reliable, manageable heat.

Premium

Premium LED

$500 – $1200

Top-bin diodes, full spectrum tuning, dimmer, often UV/IR options.

Best for

Serious enthusiasts and commercial setups.

Watch out for

Quickly becomes overkill for hobby grows.

Common mistakes

  • MistakeBuying a 'blurple' LED based on advertised wattage instead of actual PPF.

    FixWatts at the wall mean nothing if the diodes are inefficient. Look for PPF (µmol/s) and µmol/J ratings — the real performance numbers.

  • MistakeRunning LEDs too close to the canopy.

    FixEven cool-running LEDs cause light burn within 12 inches. Start at 24 inches and dim down as you learn the device.

  • MistakeUnderestimating HPS heat in summer.

    FixA 600W HPS in a small room can push temps past 90°F without serious ventilation. LEDs solve this for free.

  • MistakeComparing prices without operating costs.

    FixAn LED that costs $300 more than an HPS often pays for itself in electricity savings within 2 grow cycles.

  • MistakeBuying based on Amazon star ratings without checking diode brand.

    FixReputable LEDs name their diodes (Samsung, Bridgelux, Osram). Cheap LEDs hide the diode source.

The full guide

How LEDs caught up. Until around 2018, HPS clearly outperformed home-grade LEDs. Then diode efficiency took a leap, and quantum board designs replaced inefficient blurple panels. Today, premium LEDs from brands like HLG, Mars Hydro and Spider Farmer match or exceed HPS yields per watt.

Spectrum advantages. Plants use red light heavily in flowering and blue light in vegging. HPS is locked into a yellow-red dominant spectrum. Tunable LEDs let you push blue during veg and red during flower for measurably better growth.

The HPS argument that still holds. If you're growing once a year and can't justify $400 up front, a $150 HPS kit grows plants competently. The electricity hit is real but tolerable for one-off grows.

Hybrid setups. Some advanced growers use LED for veg and HPS for flower to combine LED efficiency with HPS penetration. The marginal yield gain is small and rarely worth the complexity for home setups.

What to actually buy. For a 2x4 tent, a 240W quantum-board LED from a reputable brand is the modern default. It pulls about 240W at the wall, runs cool, lasts a decade and yields comparably to a 400W HPS at half the electric bill.

See our other home grow equipment guides linked below to round out your setup.

Common Questions

Are LED grow lights really better than HPS?

For most home growers, yes. Equivalent-output LEDs use less electricity, generate far less heat and last much longer. HPS still wins on up-front cost.

How many watts per square foot for cannabis?

Roughly 30-40 actual wall watts per square foot of canopy for flowering with quality LEDs. HPS needs 40-50W/sq ft to produce comparable results.

Do I need UV lights for cannabis?

Not strictly. UV-A and UV-B can boost trichome production in late flower, but they're a refinement, not a requirement. Master the basics before adding UV.

Can I use shop LED lights to grow?

Standard shop LEDs lack the spectrum and intensity for flowering. They can support seedlings or clones briefly, but flowering requires purpose-built horticultural LEDs.

How long do LED grow lights last?

Quality LEDs are rated for 50,000+ hours — that's 17+ years at 8 hours/day. Drivers may fail sooner; diodes themselves rarely do.

Our future picks

We're hand-picking the gear we actually recommend in each tier. Real product picks and trusted retailer links will appear in the slots below.

Affiliate Slot 1

Recommended budget HPS kit

Complete 600W HPS kit for cost-focused first grows.

Recommendation coming soon

Affiliate Slot 2

Recommended mid-range LED

240W quantum board LED for a 2x4 tent.

Recommendation coming soon

Affiliate Slot 3

Recommended premium LED

Top-bin tunable LED for serious growers.

Recommendation coming soon

Disclosure: Chill420 may earn a commission on qualifying purchases through links added to these slots in the future. Editorial picks are independent.

Frequently asked

Are LED grow lights really better than HPS?

For most home growers, yes. Equivalent-output LEDs use less electricity, generate far less heat and last much longer. HPS still wins on up-front cost.

How many watts per square foot for cannabis?

Roughly 30-40 actual wall watts per square foot of canopy for flowering with quality LEDs. HPS needs 40-50W/sq ft to produce comparable results.

Do I need UV lights for cannabis?

Not strictly. UV-A and UV-B can boost trichome production in late flower, but they're a refinement, not a requirement. Master the basics before adding UV.

Can I use shop LED lights to grow?

Standard shop LEDs lack the spectrum and intensity for flowering. They can support seedlings or clones briefly, but flowering requires purpose-built horticultural LEDs.

How long do LED grow lights last?

Quality LEDs are rated for 50,000+ hours — that's 17+ years at 8 hours/day. Drivers may fail sooner; diodes themselves rarely do.

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