Frequently Asked Questions
What are LED grow lights?
LED grow lights utilize LED technology to grow indoor plants and other greenhouse crops. LEDs offer many benefits that traditional grow lighting, such as high-pressure sodium, metal halide, and fluorescents, do not provide.
What are the benefits of LED grow lights?
- Boosted growth, density, and resin production; tighter internodal spacing
- Long bulb life; 50,000-100,000 hours (5 to 10+ years of consecutive use)
- Energy efficient (30-50% more efficient than traditional lighting)
- Lower heat-load / Reduced HVAC costs
- No ballasts or reflectors, additional cooling equipment, or bulbs to replace
- Spectrum, dimming, timing control (some fixtures)
- Low profile (ideal for tiered racking systems)
- Easy 'Plug-and-Play' setup
- Safe to operate; No mercury
How many watts of LED power do I need compared to HID lighting?
Generally, 30-50% less wattage is needed depending on the efficiency of the LED grow light. More efficient grow lights exude more light while using less watts. Remember, that this is actual LED wattage, also known as wall wattage, not the advertised LED wattage that might be found in the title of the LED grow light. For example, an advertised '1200W' LED grow light might only draw 500W at the wall.
How many watts do I need per square foot of grow space?
You will want around 30-40 watts of actual wattage per square foot of grow space. Some LED grow lights require less, while others require more depending on the efficiency. It is best to follow the manufacturer's recommendation because all LED units are designed differently. See this article to learn more.
You shouldn't actually use wattage to determine how powerful of an LED grow light you need. Instead there are other factors that are more important, such as PPFD and footprint uniformity.
What is PPFD and why do I need to know about it?
PPFD (photosynthetic photon flux density) is a measure of the number of photons in the 400-700nm range of the visible light spectrum that fall on a square meter of target area per second. High PPFD numbers are good, because this means your plant is 'absorbing' enough light to carry out important physiological processes. Keep in mind that there are LED lights that have high wattages, but could have low PPFD numbers due to many factors such as: wide beam/lens angles, large distance between LEDs, an increased height above the canopy, low efficiency, and so on.
The fixture's average PPFD will tell you how much light the unit is putting out over the specified area.
Check out our starter's guide which covers the important metrics for choosing an LED grow light.
How far away should I setup my LED grow light from the plant canopy?
Recommended distances may vary based on the brand, light shape, coverage area, beam angle, etc. These factors all affect the Photosynthetic Active Radiation (PAR) that contacts the plants leaves. The best advice is to follow the manufacturer's recommendations for their light as they will all be slightly different. But generally, 18"-36" is a typical distance: 18" for flower and 24" or more for veg.
Can I veg with HID and flower with LEDs?
This is not recommended. Since the plants are used to a particular light intensity and spectrum, switching promptly between lighting sources could shock the plant and delay flowering. It is not unlike growing a plant indoors and placing it outside for the first time without gradually exposing it. It is more assuring to veg and flower with a single spectrum.
What is your return policy?
Please see our return policy here.
What payment methods do you accept?
American Express, Visa, MasterCard, Discover, PayPal, Sezzle, ViaBill, Venmo. We also accept money orders and bank transfers.
Will you match competitor's prices?
Of course! Read more about our low price guarantee here.
Can I order through email?
Can you ship to a P.O. Box?
Yes. However, a residential or business address is preferred when placing an order. Mars Hydro and Spider Farmer products cannot be shipped to a P.O. Box.
How do I cancel my order?
Contact us as soon as possible if you need to cancel your order. If your order has already been processed or sent out, a 10-20% restocking fee may be deducted from your refund.
How long does it take for my order to arrive?
We ship most lights using standard ground shipping. Due to the variety of brands, the lights will ship from different warehouses. After the order is processed, we send most orders out within 1-3 days. Once the item leaves the warehouse, shipping times can range from 2-7 business days depending on your location within the USA or world. If you need your light sooner, please let us know before you place your order and we will work to accommodate your needs.