Outdoors, plants thrive in sunshine which provides them with a full-spectrum light source. Indoors, you have to provide the light they need which can be anything from a sunny window to advanced lighting. Windows typically do not allow enough light through for plants to grow beyond the sprouting stage. Luckily, you have a few choices of grow lights that vary in brightness and cost to ensure your indoor hydroponic garden is as successful as possible. The right lights for you depend on your goals and your budget.
Compact fluorescent light (CFL) is a smaller, brighter version of the basic shop lights with long tubes that are in so many classrooms and basements. CFL bulbs are about the size of standard incandescent lightbulbs, but like classic fluorescents, CFLs don’t throw off much heat when they’re on. CFLs are the least expensive grow lights to buy and use. They’re bright enough for plants to grow from seedlings or clones into transplants. Leafy crops get enough light from CFLs to produce a steady harvest, but you’ll get few, if any, undersize flowers with the low-intensity lights.
Pros: Low-cost bulbs and low power use.
Cons: Not bright enough for flowers.
Best for: Growing seedlings and clones.
Light-emitting diode (LED) lights are the newest type for use in a grow room. They shine a broader range of the spectrum on plants than CFLs do, enough to produce lush mature plants that flower. LEDs are easy to set up and use. You simply plug them into the wall, no additional wiring work necessary. They’re also simple to take down, which is handy if your indoor garden isn’t in a permanent spot. LEDs remain cool while in use, even up to 24 hours a day during some stages of plants’ growth. LEDs are energy efficient compared to other grow lights, but they are the most costly option to buy.
Pros: Easy set up.
Cons: Most expensive to purchase.
Best for: Temporary grow rooms.
High-intensity discharge (HID) lights are the brightest, most effective option. They come in two distinct types: metal halide and high-pressure sodium. Metal halide bulbs are strongest in the blue range of the light spectrum, which is critical for stem and leaf growth. High-pressure sodium bulbs emit more light at the red end of the spectrum, which is vital for the plants’ blooming. You can grow flowering plants through to harvest with either type of HID lights, but if you can afford it and have room for both, the ideal is to switch from metal halide to sodium lights as the plants move from the vegetative to flowering stage. Both of these types of lighting get quite hot, and they require installing a ballast, which converts electricity from standard outlets into the voltage needed to operate these powerful lights. You need at least a basic knowledge of wiring and grounding to set up HIDs without causing an electrical fire.
Pros: Produce the most robust plants.
Cons: Need to be in a room with climate control.
Best for: Serious hobbyists with dedicated grow rooms.
Which Is Your Top Pick?
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