What is the difference between HPS, MH, CMH and CFL lamps?

HPS (High Pressure Sodium) – the ideal choice for flowering

HPS lights are the gold standard for the flowering phase of plants. They emit a predominantly red-orange spectrum of light that stimulates the formation of flowers and fruits. This makes them the preferred choice for the final stage of the life cycle of many plants, including tomatoes, peppers and, of course, cannabis.

These lamps are extremely efficient at converting electricity into light, making them cost-effective in the long run, although they may initially require an investment and good ventilation due to their high heat.

When to choose HPS?

• For large spaces where yield is a priority

• When you want the most intense and heavy colors

• For experienced gardeners who already have a good air conditioning system
  
  600W Lumii Black HPS - growth and flowering lamp - 600W combined sodium lamp with dual spectrum and E40 socket. Perfect for stimulating enhanced flowering and powerful growth!
  
  

MH (Metal Halide) – the powerful growth engine

MH lamps produce a cool, bluish light that mimics spring daylight – ideal for vegetative growth. They are especially useful during the first few weeks of plant growth, when the structure, foliage and root system are being established. A healthy vegetative growth is the foundation for successful flowering, which is why many experienced growers start with an MH lamp and then switch to HPS.

The only downside? Like HPS, they emit a lot of heat and require good cooling.

When to choose MH?

• For the vegetative stage of development

• If you grow leafy greens

• When you want strong and healthy growth at the beginning
  
  MH Grow 400w - metal halide grow lamp - Optimized Metal Halide Grow Lamps are designed for growing high-quality, natural-looking plants.
  
  
  

CMH (Ceramic Metal Halide) – the universal choice

CMH lamps are a relatively new technology that combines the best of MH and HPS. They provide an extremely broad light spectrum, close to real sunlight, including UV and IR waves. This makes them ideal for the entire growth cycle - from seedlings to flowering.

They emit less heat and have a longer lifespan than MH and HPS, but are also more expensive initially. In return, you get a stable, balanced environment for your plants that promotes both growth and quality flowering.

When to choose CMH?

• If you are looking for one lamp for the entire cycle

• For smaller spaces with limited ventilation

• When you care about quality and want to imitate natural light
  
  Par-Gro 315W CMH 3100K - ceramic metal halide lamp for growth and flowering - Spectral distribution optimized for photosynthesis efficiency and cost-effectiveness (long average life, high μmol output, low energy consumption)
  

CFL (Compact Fluorescent Lamps) – the affordable start

CFLs are compact fluorescent bulbs and are the most affordable way to get started with indoor gardening. They emit relatively little heat, don't require special ballasts, and are great for small spaces where you're growing seedlings, clones, or herbs.

Of course, they do not have the power of other types of lamps and are not suitable for the flowering stage of large plants, but for a start or as auxiliary lighting, they are an excellent choice.

When to choose CFL?

• If you are a beginner and don't want a big investment

• For growing herbs, seedlings or microgrows

• If you want a low-temperature alternative
  
  Agro Lite CFL 150W blue - grow light - The innovative part of these grow lights is their internal ballast technology and unique design, which make them ideal for humid conditions. Since they do not require an external ballast, you can simply plug them into any regular outlet. You can use them as your main light source , or for supplemental lighting for plants .
  
  
  
  
  Choosing the right grow light is key to the success of your grow project. It’s important to consider the stage of growth of your plants, the space you have, your budget, and your experience as a grower. Here’s a quick comparison:
  
  Whether you’re starting with a few pots in your closet or setting up a large grow room, the right lighting will be the backbone of your success. We hope this guide has helped you better understand the differences between HPS, MH, CMH, and CFL lamps. Next step? Check out our Lighting category to find the right models for your project!