Tomato Grow Light: Which Is Recommended For Starting Or Growing Tomatoes Indoors?

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Growing tomatoes indoors all the way is a great way to enjoy fresh, delicious fruits without having to worry about the weather (cold season) or pests.

Many home gardeners use tomato grow lights only for growing healthy, stocky tomato seedlings and then plant them outside in the full sun for the rest of the season.

Using grow lights, most of the time, is a much better option than putting seedlings in a window, where the risk of phototropism (stretching toward the sun), resulting in leggy seedlings, is quite high.

Which Are The Best Tomato Grow Lights For Home Use?

1. For all-stage growth, LED tomato grow lights are recommended because they provide an ideal spectrum of light for plants, are very bright (high lumen output), are energy efficient, and have a long life span.

2. For growing seedlings, both LED and compact fluorescent (CFL) grow lights can work fine. Both have some pros and cons, which we will discuss later on.

Overall, LED Lights Are The Best Grow Lights For Tomatoes

There are many grow lights available that make it easier to provide the light your tomato plants need. Of all the choices out there, the simplest and best to use is LED grow lights for home growers.

LED lights emit the wavelengths needed for the photosynthesis of tomato plants and are perfect for indoor gardening. Plus, they are energy-efficient and long-lasting, saving you money in the long run.

For best results, look for

  • “Full -spectrum” LEDs with a range between 5000K and 6500K (in degrees Kelvin) giving light temperatures similar to sunlight
  • Brightness of several thousand lumens per set
  • Energy efficiency: for a one-square-foot coverage, a 20W-40W consumption is fine

The Top 3 List Of Tomato Grow Lights

1. Viparspectra XS Series LEDs

They are the ideal solution for your indoor tomato gardening needs. They are among the most affordable, high-intensity grow lights on the market and come with all the features you need to grow your tomatoes efficiently.

The XS1000 and XS1500 models are very cost-effective, made with top-notch Samsung diodes, and have an amazing life span of over 100,000 hours.

The Viparspectra XS Series LEDs are a great choice when it comes to finding the best grow light for tomatoes.

They have all the features needed to help you get the most out of your indoor tomato gardening experience. With their long life span and efficient use of energy, they will be sure to keep your tomatoes growing healthy and happy!

2. The Venoya 75W LED Grow Light

This device is well-suited for indoor tomato cultivation as its 225 LEDs emit a spectrum of wavelengths from 390 nm to 730 nm, matching the optimal wavelength for plants under natural light.

The Venoya 75W LED promotes the growth of tomato plants from seed to germination, vegetative stage, and flowering, leading to quicker and healthier development.

It consumes only 27 watts of power, making it an extremely energy-efficient choice. Even better, its high quality allows it to last up to 50,000 hours of use.

You don’t really need any prior experience or expertise in setting up your own grow lights either—it’s user-friendly and provides easy setup guidelines for you.

3. Spider Farmer LED Grow Lights

The SF1000 and SF2000 sets are both great for indoor tomato growing.

They feature Samsung LM301B Diodes, which provide optimal canopy penetration, zero noise, and a long life span of more than 55,000 hours. They are suitable for all-stage growth.

The SF1000 has a coverage of 2’x2’/3’x3′ (60×60 / 90×90 cm), while the SF2000 has a covarage of 2’x4’/3’x4′ (60×120 / 90×120 cm).

Types Of Grow Lights

Fluorescent Grow Lights – Good For Seedlings, But Not For Full-Grown Tomatoes

Fluorescent lights are an economical choice that fits into most budgets, but their life span is shorter than that of LEDs, which is approx. 10,000-20,000 hours vs. 50,000-100,000 hours.

There are different types such as

  • compact fluorescent (CFL)
  • standard T12 fluorescent
  • High Output (HO) T5 fluorescent (6500K)

For growing seedlings, they may be a good choice if suspended close enough to the tops of the seedlings (within 1–3 in / 2.5–7.5 cm, with a brightness of 1,500 lumens) and turned on approx. 14 hours per day. They emit very little heat so there’s no risk of damaging your plants.

Note: Don’t break them! They contain a small amount of mercury vapor that is released into the air if broken. If you happen to break a bulb, stay away from it for a short time, only then start to clean it up.

If your goal is to grow tomatoes indoors for harvest, go for high-performance LEDs!

Fluorescent Grow Lights Pros & Cons

very affordable, good light spectrum, don’t produce much heat, energy efficientlittle less energy efficient than LEDs, suitable only for short plants (i.e. seedlings), shorter life span than LEDs, mercury hazard if broken

Worth checking out:

SunBlaster SL0900151 13 Watt CFL Grow Lamp 4 Pack

They are is simple to set up and use, making them a great choice for beginner gardeners looking to get started with indoor gardening.

HID (High-Intensity Discharge) Grow Lights

HID lights are the strongest type of plant light, but use a lot of electricity and produce a considerable amount of heat. They are commonly used by businesses, professional indoor gardeners, and large-scale growers.

HID lights are available in two types: Metal Halides (MH) and High-Pressure Sodium (HPS); MH provides lighting for all stages of growth, whereas HPS (warm-colored lights) only helps with flowers or fruits.

They are not recommended for home growing.


HID Grow Lights Pros & Cons

lower upfront costs, brilliant and consistent quality light, outstanding canopy penetrationshorter life span than LEDs, produce more heat and thus need cooling fixtures, less energy efficient, require more maintenance


LED (Light-Emitting Diode) Grow Lights

LED grow lights are the newest, most energy-efficient type of grow light. They last longer, use less electricity and come in various colors to suit your plants’ light needs. While initially expensive, these bulbs will ultimately help you cut electric costs.

LED Grow Lights Pros & Cons

very energy efficient, long life span, easy to use, run cooler, many LED sets allow spectrum controlhigher upfront costs, quality can vary by manufacturer

Light Output Depreciation: Why Is It Important?

It’s good to know that for each type of grow light, it is inevitable that some light output depreciation occurs. This means that from the first use of the light source, light output (measured in lumens) gradually decreases over its life span.

Different types of grow lights have different light output depreciation rates over their lifetime:

Fluorescent: -7%

Ceramic Metal Halide: -20%

LED: -25%

HID / High Pressure Sodium: -33%

HID / Metal Halide: -50%

You can see that fluorescents lose only 7% and LEDs lose 25% of their light output by the time they wear out.

But don’t forget: LEDs can endure 5 times longer than fluorescent lights, which gives us roughly the same light output depreciation figures: e.g. after 10,000 hours of operation, they both emit approx. 5-7% fewer lumens.

Unlike the sun, indoor grow lights decrease in performance over time. This depreciation results in less light output for your valuable indoor crops, which means a reduced overall yield with the same energy consumption.

Quick math:

If you grow seedlings indoors for 12 weeks (84 days), you use your tomato grow lights for about 1200 hours (14 hrs/day). If you use fluorescent grow lights, they will last 8-10 seasons.

If you use LED grow lights, they will last 40-50 seasons, but be aware that after 40-50 thousand hours, they will emit 15-20% less light.

Here’s a rough estimation for how long you can use fluorescent and LED lights for growing seedlings or full-grown plants indoors:

From seed to transplant (12 weeks / 1,200 hours)8-10 seasons40-60 seasons
From seed to harvest (22 weeks / 2,200 hours)4-5 seasons20-30 seasons

It looks like you can use LEDs for a long time without having to replace them…

What Features Should Tomato Grow Lights Have?

When it comes to tomatoes, you want high-quality and reliable grow lights to ensure healthy growth. LED lights are a great choice because they provide full-spectrum light that mimics the effects of sunlight on plants.

Full-spectrum lights are important for tomatoes because they provide all the necessary wavelengths needed for photosynthesis. LEDs also last longer than other types of bulbs, which means you won’t have to replace them as often.

Plus, they don’t get hot like some other types of bulbs, so you can place them closer to your plants without worrying about causing damage.

Additionally, LED lights use less energy than traditional grow lights, so even though they might be more expensive upfront, in the long run, you’ll save money on electric bills.

When shopping for a full-spectrum LED grow light, you should consider wattage, COB (chip on board) versus single arrays, and color rendering indices (CRI) as well.

You may also want to look for automated options with adjustable brightness settings and timers so that your tomatoes get the exact amount of light they need from sunrise to sunset each day, no matter what time of year it is.

LEDs can also produce more natural red spectrums, i.e. warm-colored lights, than other types of lighting which is more beneficial when trying to stimulate flowering in tomatoes specifically.

With these features in mind, LED grow lights are an easy choice when it comes to indoor gardening with tomatoes.

What Color Grow Lights Should I Use?

Tomatoes need full-spectrum light, containing both cool (blue light, 5,000–7,000 K) and warm (red light, 3,500–4,500 K) colors for healthy growth.

LEDs grow lights can be adjusted to emit different colors of light at different intensities depending on the stage of growth your tomato plant is in. They provide all the wavelengths necessary for optimum growth and yield with minimal effort on your part.

Red light is especially beneficial for flowering and fruit production while blue light promotes vegetative or leafy growth. Choosing an LED system with adjustable output allows you to customize your ratio of red-to-blue and even extend into ultraviolet or infrared if needed.

FAQ – Tomato Grow Lights

How Many Hours Of Light Do Tomatoes Need Indoors?

Indoor tomatoes need at least 12-14 hours of artificial light per day to remain healthy and productive. Without this amount of light, the plants will not be able to produce the same quality or quantity of fruit as they would if grown outdoors.
So if you’re looking for an easy way to provide your indoor tomato plants with enough light, investing in a grow light is the simplest and best option available.

Can I Leave My Grow Light On 24/7?

No, you should not leave your grow light on 24/7 for indoor gardening. Tomato plants need a dark period in order to rest and recover. If your grow light is left on all the time, it will stress out your plants.
The best way to ensure that your tomato plants remain healthy is by providing them with a consistent light schedule. This means that you should keep the lights on for 14-16 hours each day, then turn them off for 8-10 hours each night.
Doing this will give your tomato plants the energy they need without overexerting them.

Where Should I Grow My tomato Plants Indoors?

The first step is to find an ideal spot for your plants. South-facing windows are the best option as they typically receive more light even in winter months, allowing your tomatoes to get enough light throughout the year.
If you don’t have access to a south-facing window, then using grow lights is the next best option.
LED lights are definitely one of the simplest and most cost-effective solutions available today. By combining them with south-facing windows or other sources of natural light you can ensure that your tomato plants get enough sunlight throughout their life cycle without having to worry about excessive heat or expensive energy bills.

At What Temperatures Should I Grow My Tomato Plants Indoors?

The ideal temperature for growing tomatoes indoors is between 65 and 70°F (18 to 21°C). Tomatoes are OK with temperatures in the range of 60-85°F (16-29°C).
For seedlings, in order to develop healthy and stocky stems, cooler temperatures 60-68°F (16-20°C) are ideal while they get the right amount of light directly from above., i.e. using grow lights suspended just 1-3 in (3-8 cm) over the seedlings and raising the lights as the plants get taller.
Flowering is encouraged by warmer temperatures, with optimal growth ranging from 75-85°F (24-29°C).
Note: If the temperature drops below 55°F (13°C) the plant’s growth will be significantly stunted. Tomatoes will stop producing fruit if the night-time temperatures drop below 55°F (13°C) or if daytime temperatures exceed 95°F (35°C).

Can I Use Shop Lights For Growing Tomatoes?

Yes, but mainly for seedlings, if light temperature and brightness are OK. This means that your shop light, either fluorescent bulbs or LED bulbs, should have a Kelvin rating of 5,000 to 6,500 and an output of 2,500 lumens or higher.

7 Practical Tips For Growing Tomatoes Indoors

Growing tomatoes indoors can be a tricky endeavor, but the results are well worth the effort. With the proper care and good artificial light, it’s possible to cultivate lush, vibrant tomato plants that yield delicious fruits all year round.

To help you get started, here are 7 tips to ensure success with your indoor tomato garden:

  1. Find the best spot in your home – Tomatoes love plenty of direct sunlight; choose a spot next to a window that gets at least 6 hours of bright, indirect sunlight each day.
  2. Invest in grow lights – If natural sunlight isn’t available, invest in quality grow lights that offer both blue and red spectrums of light – this will provide your plants with enough energy for photosynthesis and efficient growth.
  3. Use nutrient-rich soil – Tomatoes need nutrient-rich soil to thrive; use a fertilizer specifically designed for vegetables or mix your own using composted manure or fish emulsion.
  4. Choose the right variety – Not all tomato varieties are suited for indoor growing; pick dwarf or determinate varieties as they tend to produce better yields indoors.
  5. Stake tall plants – Taller varieties of tomatoes will require staking; use bamboo stakes and tie them loosely around the stem so that you don’t damage it as it grows taller.
  6. Prune carefully – Pruning helps keep plants healthy by removing excessive foliage and allowing more air circulation; however, be careful not to remove too much foliage or else you could stunt plant growth.
  7. Avoid over-watering – Over-watering can cause problems like root rot or fungus growth; allow the top inch of soil to dry out before watering again.

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I'm a keen hobby gardener. I love growing fruits and vegetables, especially tomatoes. I'm also a certified instructor of the Square Foot Gardening Foundation.