How To Choose The Best LED Grow Light For Weed Greenhouses

Greenhouses have a “bright” perk over enclosed grow spaces: the sun! No matter how sophisticated light technology gets, it will never fully replicate the power of natural sunlight. Indeed, with such an obvious advantage, it may seem strange to add LED grow lights to a greenhouse space.

While you could grow greenhouse cannabis without extra grow lights, many cultivators like to add these units to their setup. Although LED lights will add to total energy expenditure, those costs could be offset with superior cannabis yields and unparalleled quality.

However, greenhouse cultivators can’t pick an LED WILLY-NILLY and expect great results. Specific LED models are fantastic for greenhouse settings, while other designs are suited for traditional tent cultivation. Before adding grow lights to a greenhouse, you must know what to look for in an LED.

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Why Would You Use LEDs In A Cannabis Greenhouse?

Before sharing how to pick LED grow lights for greenhouses, it’s worth reviewing why cannabis cultivators would bother installing these lights.

While LED grow lights may not be “essential” for greenhouse spaces, they allow cultivators to double their output throughout the year. Since cannabis is photoperiod sensitive, there’s only one growing season per year. However, if growers install LED grow lights, they could grow top-quality buds even in the dead of winter.

LEDs also offer an extra measure of control for growers throughout the year. Even if it’s cloudy outside, greenhouse growers could use their LED grow lights to make it “bright inside.” Plus, on sunny days, high-quality LED lights offer additional light penetration, which will help cannabis plants reach their max potential.  

What Are The Best Features Of Greenhouse LEDs? — Five Considerations

Don’t Block Sun! — Choose A Properly Fitting LED Grow Light

Ironically, a top concern associated with greenhouse LED grow lights is that they won’t block too much natural sunlight. Yes, supplemental LEDs have a lot to offer cannabis plants, but they should never steal the show. Moreover, nature offers a big amount of energy to the ground, so why not take advantage of it to save your bucks?

When evaluating LED grow lights, cultivators should ensure these lights will complement the natural sunlight. Instead of buying large LED panels, concentrate on thinner models that take up less space. For instance, the Mars Hydro SP3000 has a long and slim design perfectly suited for a greenhouse setting.

What’s The Ideal LED Spectrum For Greenhouses?  

Generally, it’s best for greenhouse growers to use LEDs with a broad spectrum of lightwaves. Since these lights have a wide range of wavelengths, they give growers the option to totally replace daylight during dark seasons and to prolong the daily lighting period. Moreover, these full-spectrum LED grow lights can be useful as supplemental lights during the spring to fall cycle.

While broad-spectrum is the ideal choice for most greenhouse growers, there are some cases where a narrowly-defined light spectrum may be all you need. You’ll need to assess your growing goals to determine which light spectrum best suits your cultivation strategy.

Search For Adequate Light Penetration

A key reason people use LED grow lights is to shine extra light on every potential bud site. It’s common for the cannabis plant’s main colas to hog all the sunlight and block bud sites near the bottom. Targeted LED grow lights are a fantastic tool to increase light exposure.

Though with LEDs in the proper position, there’s less need to fear lower buds won’t get the light they need to grow beyond “popcorn” size, to ensure an LED grow light has superior light penetration could be the easiest path. An LED grow light could penetrate through most of the leaves and carry PPFD into deeper canopies when the light intensity and spectrum are specially designed. Ideally, your LED spectrum should have high concentrations of Infrared, far red, and blue wavelengths to improve photosynthesis.

Look For A Dimmable Feature

A great greenhouse LED grow light should have a dimmable feature and superior light penetration. Remember: A key reason you’re adding LED grow lights to your greenhouse is for extra control. Without a reliable dimmer, you’d have no way of controlling your greenhouse’s internal environment.

With responsive dimmer controls, you can adjust light intensity depending on the day’s conditions. Cultivators could also match their suggested daily light integral (DLI) without extra labor to move around lights. 

Considerations About Heat Dissipation

Unlike other indoor grow spaces, greenhouses experience substantial temperature swings. The extra sunlight during the day drives temps up, while its absence at night could make your room extra chilly. Although there are plenty of tools cultivators could use to control temperature and humidity in greenhouses, a bunch of heat coming from grow lights would still arise thermal management costs. And with the lights off, the heat from the lights dissipates quickly, which can also stress the plants.

Cultivators should focus on LED grow lights that won’t mess with their well-calibrated temp & humidity setup. Also, if you’re not careful, poor-quality LED grow lights could damage sensitive buds with excessive heat.

Thankfully, light-emitting diodes usually aren’t as “hot” as HPS bulbs. And LEDs with heat sinks avoid heat aggregation that would damage both crops and lights.

Cultivators should review any ambient temperature concerns when reviewing LED grow lights. LED grow lights with thick passive heat sinks are proved to be effective in heat dissipation and convenient in light maintenance. It’s an essential feature for any commercial greenhouse lighting.

Do Mars Hydro LED Grow Lights Work In Cannabis Greenhouses?

Many weed growers first hear about Mars Hydro’s LED grow lights for enclosed indoor spaces. However, customers should know we also offer greenhouse-specific models. Unlike our standard LED panels, Mars Hydro SP series LED grow lights are slim enough to add supplemental light without blocking the sun.

If you’re looking for an LED grow light tailored for a greenhouse, we’d recommend starting with Mars Hydro’s SP3000 or SP6500. Both of these greenhouse-friendly LEDs have many advanced features like Samsung LM301B diodes, dimmable switches, broad-spectrum wavelengths, thick passive heat sinks, and most importantly, superior light penetration.

If you have any concerns about adding LEDs to your greenhouse, please reach out to the Mars Hydro team. We now have manufacturing facilities in all Western nations, including the USA, Canada, Australia, the United Kingdom, and Europe. Please email info@mars-hydro.com or visit this Contact Us page to send a note to Mars Hydro. We’ve also designed a Greenhouse Lighting page FYI.