Breaking Down the LED Types: Blurple vs. White, Pink & Red

Breaking Down the LED Types: Blurple vs. White, Pink & Red

LED Grow Lights for Hydroponics: Narrowband vs. Broad Spectrum

When researching horticultural lights for indoor and hydroponic grows, you’ll encounter two main types of LEDs: those that emit a specific color (narrowband) and those that emit a broader range of hues (often perceived as white). This guide explains each type and helps you choose the best LED approach for your crops’ needs without changing the original conclusions.

Narrowband (Monochromatic) LEDs

Narrowband LEDs produce a very tight emission spectrum—typically red or blue. Because red diodes are highly efficient at converting electricity into photons, many fixtures weight their output heavily toward red. Used alone for too long, high-red mixes can encourage elongated, spindly growth—especially in flowering crops—so balancing spectra matters.

Broad-Spectrum (White) LEDs

Broad-spectrum (white) LEDs deliver a wider range of wavelengths. Most “white” LEDs start as blue diodes with a phosphor coating that converts part of the blue into longer wavelengths. There’s no “white wavelength” in physics—the effect is a blend of red, green, and blue that appears white to the eye. Broad-spectrum fixtures better mimic natural sunlight and support both vegetative and flowering phases effectively.

Why So Many White LEDs on the Market?

Most LEDs were first designed for people, not plants, so white LEDs became the standard. As blue (phosphor-converted white) LEDs dropped in price, manufacturers increasingly used them for both human and horticultural lighting. Today, white options are abundant and cost-effective while still serving plant needs well.

Common Horticultural LED Fixture Types

Purple (Blurple) LEDs

“Blurple” fixtures combine red (about 75–90%) and blue (about 10–25%) diodes. The mix looks pink-to-purple and delivers strong energy for photosynthesis, favoring vegetative and flowering phases. They’re popular for energy savings and affordability, but the heavy red emphasis can promote lanky growth over time if not balanced. Blurple light can also make workspaces visually unpleasant and makes it harder to spot pests or disease because foliage no longer looks green to the human eye.

Pink LEDs

Pink fixtures blend white and red LEDs. They’re generally less energy-efficient than blurple but create a softer, more natural-looking workspace. Depending on the ratio, some pink fixtures can lean more purple. Pink can be a good compromise when you want better human visibility than blurple while still meeting plant needs.

White LEDs

White-LED fixtures primarily use white diodes; some brands add a small percentage of red or other colors. Always check labeling to confirm the spectrum mix.

  • Cool white: Slight bluish cast; crisp, subtle.

  • Warm white: Rosy, comfortable glow; pleasing for most people.

  • Mint white: Greenish hue; plants “pop,” but skin tones look off.

White LEDs are easier on the eyes and generally more effective for growing and flowering than pink or purple fixtures. Although pure white solutions are not as energy-efficient as tightly tuned red/blue mixes, their broader spectrum tends to produce more natural, compact growth and better overall performance across a plant’s life cycle.

Red LEDs

Red diodes are extremely efficient and excellent at driving photosynthesis in the short term. However, too much red—especially without blue or far-red context—can encourage leggy growth. Fixtures with a balanced red/blue mix produce sturdier, more compact plants. Note that white LED solutions often include some far-red content, which can slightly increase plant height and may hasten flowering compared to strict red/blue mixes without far red.

Which LED Type Is Best for Your Crops?

Blurple fixtures are cost-effective and energy-efficient, which explains their popularity. Still, full-spectrum (broad-spectrum) LEDs generally provide the best plant development and the most natural working environment. Full-spectrum LEDs usually cost more and may not match the raw efficacy of narrowband red/blue mixes, but they still use less energy than legacy white lighting like MH, HPS, or CMH and deliver strong results for both veg and flower.

If full-spectrum remains outside your budget, pink fixtures can improve visual comfort over blurple while adequately supporting growth. For many hydroponic growers, that balance of plant performance and human-friendly light is worth it.

Actionable Takeaways for Growers

  • For overall crop quality and ease of scouting, choose full-spectrum (white) LED grow lights.

  • If budget is tight, pink LEDs offer a practical compromise between plant performance and a comfortable workspace.

  • Use red/blue (blurple) LEDs for efficiency, but watch for elongated growth and harder pest/disease visibility.

  • Aim for a balanced red/blue ratio to maintain compact, sturdy plants; avoid excessive red dominance over long periods.

  • Expect white LEDs to contain some far red, which can slightly increase plant height and may accelerate flowering.

Conclusions

The best LED grow lights for most hydroponic applications are full-spectrum LEDs because they emulate natural sunlight and support all growth phases effectively. While blurple fixtures save energy and cost less, they can compromise human visibility and encourage undesirable elongation if overused. Pink fixtures are a reasonable middle ground when you need a friendlier work environment without sacrificing core plant needs.

Back to blog