UV420 Plasma Grow Light

The UV420 HEP plasma grow-light, developed by Ceravision, is a leap forward in horticulture supplementary grow-lighting.  The UV420 plasma grow-light has completed compliance testing to all relevant international standards by independent laboratories and is now CE marked.

To order the UV420 please click here.

For all commercial enquiries please click here.

This unique plasma grow-light delivers blue light UV-A and UV-B - all essential for stronger, faster vegetative growth and more resinous, higher yielding crops.  Output can be adjusted to deliver the optimum amount of supplemetary light, tailored to the growing cycle.  Crops grown under UV420 grow-lights will produce higher levels of terpenes, essential oils and flavonoids.  The UV420 has attracted much interest from the hydroponics sector including as a cannabis grow-light. 

 UV420 Plasma Grow-Light Delivers Enhanced Performance
Total Light Delivered Over 2.0m2
Other Plasma - 56 Watts CMH - 77 Watts UV420 - 115 Watts
  Distribution   Distribution   Distribution
  Blue 50.7 90%   Blue 72.6 94%   Blue 87.4 76%
  UV-A 5.5 10%   UV-A 4.54 6%   UV-A 22.5 20%
  UV-B .05 0%   UV-B 0.0005 0%   UV-B 4.8 4%


The dose in the UV420 plasma grow-light consists of metal halides that are completely evaporated.  This removes any potential for degradation on the inner surfaces of the capsule during operation and allows for lamp life in excess of 25,000 hours. Other plasma technologies and metal halide lamps suffer from material stress of the capsule caused through chemical reactivity of the metal halide liquid pool which is a precursor to failure and reduced life (see diagram below).

UV420's Patented Dose Provides Extended Life and a 2-year (12,000 hrs) Warranty
   Metal Halide      Other Plasma    


  Electrodes Yes No No
  Metal halide Yes Yes Yes
  Chemical reactivity High High Low
  Material Stress Medium High Low
- UV-A - Low High
- UV-B - Low High
- Blue High Medium High
  Maintenance High High High
  Dimmable No No Yes


The UV420 Plasma Grow-Light is a Perfect Supplementary Grow-Light

The quantity and wavelength of light reaching the crop can be modified according to the reflector glass used:

  1. Standard Glass: has a lot of blue and green light and little UV-A and UV-B (black line in charts);
  2. Enhanced UV: has increased UV-A and UV-B (red line in charts below); and 
  3. Enhanced UV+: has maximum UV-A and UV-B (blue line in charts below).
 UV420's Relative Light Qantity from 200nm to 800nm​Plot showing the light spectrum wavelengths of UV420 HEP Plasma growlight


 UV420's Relative Light Qantity from 260nm to 400nm​Plot of UV420 HEP grow light spectrum showing UV-A, UV-B and blue light wavelengths.


The chart below shows the more complete spectra offered by the UV420 in respect of the chlorophyll ‘a’ and ‘b’ receptors in plants.

Photosynthetic Pigments and the UV420 Spectrum cf HSP (source Ceravision)

HEP Plasma Grow Light spectrum, photosynthetic pigments and an HPS spectrum.


HPS, LEDs & UV420 Plasma Supplementary Grow-Light

Full continuous spectrum with sunlight qualities is the best for healthy plant development.  Plants absorb light best at specific peaks in blue and red spectra (465nm and 665nm).  UV-A (315 - 400nm) and UV-B (280 - 315nm) influence photomorphogenic plant responses including gene regulation, flavonoid biosynthesis, leaf and epidermal cell expansion, stomatal density, and increased photosynthetic efficiency.  Exposure to UV-A and UV-B also induces the synthesis of specific proteins involved in resistance to microbial attack. 

Plants grown outdoors are subject to varying amounts of UV-A and UV-B depending on geographical location and time of year.  Unlike other supplementary grow-lights, the UV420 plasma grow-light delivers these benefits.  In cannabis, anecdotal evidence shows that UV-A and UV-B delivers increased production of cannabinoids including CBD and THC and raises resin production by 20%.  

  • HPS provides an efficient source at the red-end of the photosynthetically active radiation (PAR) region, but does not produce usable blue light - UV-A or UV-B, or green light, lacking the high energy range below 560nm
  • LEDs are mono-chromatic and do not have a full spectrum similar to the sun, which can lead to inhibited plant growth; they also lack UV, essential for optimal plant growth and development
  • Metal halide (MH), Ceramic metal halide (CMH) or Fluorescent lighting can help to increase the blue spectrum; however neither offer very much UV light.   

Good Reasons to Choose the UV420 Plasma Grow-Light

With a spectrum from 280 to 550 nm, the UV420 plasma grow-light produces intense visible blue light, UV-A and UV-B, and green light, and filters out harmful UV-C, the UV420 may be the most efficient supplementary grow-light around:

  • Faster rooting, stronger, faster germination, vegetative growth, flowering and resinous, high yielding cropsCeravision's UV420 supplementary plasma grow light on a tomato harvest
  • Protection from moulds and mildew and near elimination of pests
  • Improved pollination from pollinators attracted by the UV now on the flowers
  • Increased terpenes, essential oils and flavonoids plus abundant trichome production
  • Low maintenance, low running costs and compatible with existing contactors and timers
  • Small light source, compact luminaire and minimal shadowing
  • Uniform distribution of 2.0sq.m at hanging height of 2.0m and good penetration in hi-wire crops
  • Easily changed reflector for blue and green light with UV-A and UV-B options to suit growth stage
  • Low lamp degradation, 50,000hrs+ magnetron life and a tough, durable casing
  • Complementary grow-light used with HPS and LED to maximise plant development
  • Ideal grow-light for high value crops including cannabis.

 Light Distribution

Technical Data

 Product Name    Ceravision UV420W
 Manufacturer    Ceravision Lighting Limited
 Power Consumption    430 Watts
 Mains Supply Voltage    110-240 Volts at A/C 50-60 Hz
 Weight    10kg
 Dimensions    400 x 400 x 195mm
 Ambient Operating Temperature    0ºC  to 35ºC


Sales Contacts

  • Commercial enquiries: please contact Deborah Leaper,  Sales Administration: deborah.leaper@ceravision.com.
  • UK Retail Sales: please contact The Greenhouse Effect on 01908 585283, email: info@ghedirect.com; visit The Greenhouse Effect, please click here.
  • Europe and Rest of World: please contact Sales at Ceravision, email: sales@ceravision.com.

Further Information

Future Applications

Offering flexible spectral outputs, Ceravision's HEP plasma lighting offers added-value and economic solutions in horticulture grow-lighting and other commercial applications.

HEP Plasma Lighting Technology

Ceravision’s HEP plasma grow-lights, with a unique spectrum providing essential blue, UV-A, UV-B and green light, herald a new future for horticulture lighting; and they can be tailored to suit different plants and outcomes.

Intellectual Property

Ceravision maintains an extensive Intellectual Property (“IP”) portfolio comprising Patents, Trade Marks and Design Rights.

Featured News

Ceravision is now a member of UV4Plants - the recently formed International Association for Plant UV Research


Ceravision delivering the first of its UV420 plasma UVA and UVB Grow-lights to The Greenhouse Effect


Ceravision's new UV420 plasma grow-light is shown at Autopot Summer Social 18th - 19th August 2018.