Hydroponics DIY: How and Why to Grow Indoors

For all gardeners, you already know the difficulties of growing outdoors: the constant heat that wilts your plants and makes gardening almost unenjoyable, the weather that can change in an instant—bringing a heatwave or heavy downpours—or that huge garden spider that has built a nest and wrapped itself around your rosemary bush. With all these variables, it’s no surprise that outdoor gardening can drive you crazy, and why moving your plants indoors isn’t as crazy as it sounds. While this isn’t an in-depth guide, we’ve gathered the key points you should keep in mind when starting your first indoor growing setup.

Hydroponics?

So what exactly is hydroponics? Hydroponics is the art and science of growing plants indoors using all kinds of growing media—from grow rocks, clay pellets, rockwool, soil, coconut fiber, to soil-less mixes. The great thing about hydroponics is that there is no fixed method of growing and no limit to what you can grow. Some people grow vegetables to have completely organic produce free from pesticides, while others grow indoor crops simply as a hobby. Moreover, hydroponics gives you the freedom to grow whatever you want, whenever you want. Whether it’s 15°C with three feet of snow on the ground or 110°F with 90% humidity, your indoor garden remains unaffected.

Where to Begin?

First, decide what type of plant you want to grow. Do you want to grow non-flowering herbs like cilantro or basil, or do you want to grow flowering plants like vegetables? The layout of your system will depend on the type of plant you choose. For example, if you want to grow vegetables or flowers, you’ll need a 400-watt HID grow light with both HPS and metal halide bulbs for different growth stages. For non-flowering plants like basil and cilantro, you can use T5 grow lights throughout the entire growth cycle. Commercial growing will require larger coverage areas provided by multiple 1000-watt HID lights.

Note: Because hydroponics can be a bit complicated, we’ll save many details—such as light coverage—for a later section.

As we learned in elementary science, plants need light to grow. When growing indoors, you must provide your own sunlight in the form of HID lights (High-Intensity Discharge), which include High-Pressure Sodium (HPS) bulbs and metal halide bulbs. There are also LED grow lights, which, like household LEDs, use less electricity and last longer than other types of bulbs.

Plants go through stages: the growth stage, also known as the vegetative stage, and the flowering stage, also known as the budding stage. Each stage requires a different color temperature to thrive: the vegetative stage requires a color temperature of 5000K or higher because it produces the blue portion of the spectrum, while the flowering stage requires a color temperature around 2000K, which produces light in the red spectrum—ideal for this phase.

Just as the sun doesn’t shine 24 hours a day, your grow lights shouldn’t either. For the growth cycle, lights should be on for 18 to 20 hours, then reduced to only 12 hours during the flowering stage. The easiest way to control lighting is by using a timer. A timer simplifies the entire growing process and eliminates the risk of forgetting to turn the lights on or off.

Now let’s talk about LED grow lights. There are many different types, from parabolic LEDs to wing-style LEDs, all-in-one LEDs, and air-cooled LEDs, and each type has its own advantages. For example, wing-style LEDs have adjustable “wings” that increase light coverage, helping reduce the number of dark spots. Not to mention, they are often cheaper. All-in-one LEDs include everything you need besides the bulb, such as the ballast—you simply plug them in and use them. Air-cooled LEDs have ducts on each end to cool the tube, and they are defined by the diameter of these ducts, ranging from four to eight inches (10 to 20 cm). These types of LEDs are usually intended for professional growers because they require proper ducting for cooling. The type of LED grow light you need depends on the size of your growing area.

Start Small

Before rushing into setting up a professional grow space, it’s best to start small. Try an all-in-one hydroponic kit such as Emily’s Garden. This kit comes with everything you need to start a small but successful grow: grow medium, seed-starting plugs, and even nutrients. Although it may sound simple, this is a great way to familiarize yourself with the world of indoor gardening.

For a great grow-light experience, check out the Jumpstart T5 reflector light. Available in heights from 60 cm to 1.2 m, this reflector light includes the bulb and accessories, and it can be adjusted as your plants grow taller.

Note: For more information on indoor gardening, see our hydroponics book.

Which Grow Light Should You Use for Hydroponics?

So you’ve decided to grow plants indoors. Maybe you want to grow flowering tropical plants in your office or start a small greenhouse in your backyard. Or perhaps you simply want to keep that houseplant you’ve been caring for over the past six months looking its best. No matter what you’re growing, your green friends need light. But which grow light should you use?

“Watts” – What’s the Difference Between Grow Lights?

Choosing a bulb comes down to three basic types: Fluorescent, HID, and LED. The factors to consider are watts, lumens, and operating temperature.

Watts measure the amount of energy required to run the bulb, while lumens measure how much light is produced. Lumens per watt determine efficiency. HID (High-Intensity Discharge) lights are the brightest, while LEDs are the most efficient.

Different lights also have different operating temperatures. The hotter the bulb, the farther it needs to be from your plants to avoid burning both you and the plant. The rule of thumb is to keep the light as close to the plant as possible to maximize illumination. Remember: the farther the light is from the plant, the lower the light intensity. Fluorescent bulbs operate at the coolest temperatures.

Here’s a quick rundown.

CFL Grow Lights

CFL grow lights are a compacted fluorescent tube, compressed down to the size of a standard incandescent bulb.

A 23-watt CFL is equivalent to a 100-watt incandescent bulb, producing 1600 lumens. This brightness is enough to light any traditional houseplant if placed close enough. They’re a great choice for offices and small living spaces because they’re compact enough to fit into most standard fixtures and won’t burn your plants or your skin when touched.

Mogul Base (E39) CFL grow lights may look bulky, but they offer the advantage of having the ballast built directly into the base. Although initially more expensive than similar metal halide bulbs, they’re ideal for shops, propagation benches, and small grow areas.

T5 Grow Lights

T5 fluorescent grow lights come in various lengths, but their true advantage is that their fixtures can be under 7.5 cm tall. This is perfect for maximizing vertical grow space by stacking multiple tiers of grow lights on shelves. They’re the most efficient standard fluorescent available (using about 24 watts for 2000 lumens). They provide excellent light distribution when paired with reflectors and are more efficient than mogul-base CFLs.

Metal Halide Grow Lights

MH grow lights are the industry standard. With very high output, they’re well suited for large grow rooms and greenhouses. Metal halide bulbs are more efficient than fluorescent, incandescent, and CFL bulbs of the same wattage. They are often compatible with dimmable ballasts.

HPS Grow Lights

HPS grow lights are widely used for outdoor area lighting, large grow rooms, and greenhouses. These bulbs are likely the most efficient HID lights available, though they are initially more expensive than CFL or MH bulbs.

Dual-Arc Hybrid Grow Lights

What happens if you take a 400W MH lamp and a 600W HPS lamp and smash them together? Hint: the answer is not shattered glass or a gas leak. In fact, it’s a dual-arc hybrid bulb. It contains both MH and HPS lamps in the same bulb. While they fit into the same fixtures as the original lamps, hybrid arc bulbs are significantly more expensive than MH or HPS bulbs of the same wattage. Their advantage is that they deliver both red and blue light evenly across the grow area, making them ideal for large grow rooms and greenhouses.

Double-Ended HID Grow Lights

Double-ended HID bulbs share most advantages and disadvantages with single-ended bulbs, with a few differences. Although they require special double-ended fixtures, they can use the same ballasts as standard MH/HPS bulbs. They are also more efficient, so with the same number of bulbs and ballasts, you get more light output. They’re pricier, but you can use fewer lights for the same illumination.

LED Grow Lights

LED grow lights are excellent for propagation, herbs, and leafy greens. They come in many varieties—different sizes, colors, and configurations. LEDs typically use red and blue diodes combined into an array to maximize plant growth and take advantage of the full spectrum. More efficient than any HID light, LEDs save a lot of money over time, though they’re among the most expensive options upfront.

No matter what you’re growing indoors, there’s always a bulb that fits your plant’s needs and your budget. Don’t stress about your grow lights. If you have any questions about which bulb, ballast, or reflector you need, our experienced staff is ready to help. Explore more grow lights, accessories, and more on our page in here: LED Grow Lights.

What do you plan to grow in your indoor garden? Let us know in the comments below.

See more information about hydroponic growing systems available here: Gardening with Hydroponic systems