9 Best Four Foot Grow Light Bulbs (October 2026)
The best four foot grow light bulbs include the VIVOSUN T5 Grow Light Bulbs 4Ft for 6500K T5HO replacement, the VIVOSUN T5 Grow Light Bulbs 2Ft for matching shorter T5 fixtures, and the PARMIDA 20 Pack UL 4FT LED T8 for flexible T8 LED conversion.
On this page (6 sections)
The best 4 foot grow light bulbs for a compatible T5HO fixture are the VIVOSUN T5 Grow Light Bulbs 4Ft, a 54W fluorescent tube rated at 6500K. For a standard socket instead, compare SANSI grow light bulbs.
Check the fixture's lamp type, length, base and wattage first, because a four-foot T8 replacement is not interchangeable with a T5 grow bulb.
A tube marked “4 ft” may measure about 45 to 46 inches, while a general-purpose T8 tube may measure 48 inches. Match the code printed on your old bulb and the fixture label before replacing it.
Our picks at a glance
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Best for matching shorter T5 fixturesVIVOSUN T5 Grow Light Bulbs 2Ft
9.6/10 our score
See it on Amazon -
3
- 4
Check itJESLED T8 LED 4FT Type A+B Light
Best for brighter T8 LED tubes - 5
Best for T5HO bloom spectrumCheck it - 6
Check itLightWise LWF54T5HO865 8pack 4 FT 6500K T5
Best for a multi-bulb veg setup - 7
Best for a smaller T5HO grow packCheck it - 8
Check itArikit SunBESTer 4FT 54W T5 HO 6500K
Best for 6500K T5 tubes in a five-pack - 9
Check itKonideke F32T8/841 32W 48 Inch T8 Fluorescent
Best for general T8 fluorescent replacement
Which four foot grow light bulbs suit each fixture?
The best replacement depends on the fixture, not just the nominal length. Choose T5HO fluorescent tubes for a compatible T5HO grow fixture, and consider T8 LED or fluorescent tubes only when the fixture calls for T8 lamps.
VIVOSUN T5 Grow Light Bulbs 4Ft: Best for 6500K T5HO replacement
- 54W fluorescent
- 6500K
- 5000 lumens
- 5-pack
A 54W, 6500K T5 fluorescent tube for a compatible four-foot T5HO fixture. The five-pack suits replacements where the fixture takes the 46-inch HO lamp.
Pros
- 6500K color temperature
- 54W output
- Five bulbs per pack
Cons
- For compatible T5HO fixtures
- Not a T8 replacement
VIVOSUN’s 46-inch tube is the clearest match here for a compatible 54W T5HO fixture. Its 6500K light and 5000-lumen output suit growers looking for a cooler fluorescent option.
The five-pack can be useful when you need several replacements at once. VIVOSUN gives an average recommended usage life of more than 20,000 hours and says the tubes have low heat emissions.
Check the G5 base and fixture’s lamp label before buying. A tube with the right nominal length can still be the wrong lamp if the fixture expects a different base, wattage or technology.
VIVOSUN T5 Grow Light Bulbs 2Ft: Best for matching shorter T5 fixtures
- 24W fluorescent
- 6500K
- 2000 lumens
- 5-pack
This shorter VIVOSUN T5 option is 22 inches long and rated at 24W. It can help if you have a two-foot fixture, but it is not a four-foot replacement.
Pros
- 6500K color temperature
- Five bulbs per pack
- Useful alternative for a two-foot fixture
Cons
- 22-inch tube does not fit a four-foot fixture
- 24W rather than 54W
This shorter VIVOSUN T5 bulb is included as a fit comparison, not a substitute for a four-foot tube. At 22 inches and 24W, it belongs in a compatible two-foot fixture.
The 6500K color temperature and 2000-lumen output give it a similar cool-white growing profile to the four-foot VIVOSUN. Its five-pack may suit a shorter fixture with several lamps.
Measure your fixture before choosing it. For more shorter-fixture options, compare our best 2 foot grow light picks and best feit electric led grow light 2 ft.
PARMIDA 20 Pack UL 4FT LED T8: Best for flexible T8 LED conversion
- 18W without ballast or 20W with ballast
- 5000K
- 2200 lumens
- 20-pack
A four-foot T8 LED tube with plug-and-play and ballast-bypass installation options. Check ballast and socket compatibility before choosing an installation method.
Pros
- Can work with or without a ballast
- Single or double-ended connection options
- UL-listed
Cons
- Compatibility checks are needed
- Not a T5 grow tube
PARMIDA is a four-foot T8 LED tube for fixtures that accept T8 replacements. The hybrid design supports plug-and-play use with a compatible ballast or ballast-bypass installation, with an 18W rating without a ballast and 20W with one.
Its 5000K color and 2200-lumen output make it a general lighting alternative to fluorescent T8 tubes. This is not a T5HO grow lamp, so don’t choose it solely because the old tube is four feet long.
PARMIDA notes that ballast compatibility matters. The guide to regular fluorescent lights vs grow lights explains how general tubes differ from plant bulbs.
Its single-ended setup requires non-shunted sockets, and the company recommends a qualified electrician for ballast-bypass installation.
JESLED T8 LED 4FT Type A+B Light: Best for brighter T8 LED tubes
- 24W
- 6000K
- 3200 lumens
- 4-pack
A four-foot T8 LED tube rated at 3200 lumens and 6000K. It supports ballast and bypass installation, with ballast compatibility to check before use.
Pros
- 3200-lumen output
- Plug-and-play or ballast-bypass options
- Four tubes per pack
Cons
- Not compatible with dimming ballasts
- Not a T5 grow tube
JESLED offers another four-foot T8 LED option, with a stated 3200-lumen output and 6000K color temperature. It supports plug-and-play or ballast-bypass installation, but it is not compatible with dimming ballasts.
The four-pack may be useful for replacing several tubes in a matching fixture. For a complete fixture from another brand, compare Feit Electric grow lights.
Check whether your fixture uses T8 lamps and whether the ballast is compatible before choosing the installation method.
For a broader comparison of replacement tubes, see Best LED Grow Light Replacement Bulbs. If you're deciding between LED and fluorescent technology, our guide explains What Is the Difference Between LED and Fluorescent Grow Lights?.
AgroMax 8-Pack 4 Foot: Best for T5HO bloom spectrum
- 54W fluorescent
- 3000K bloom spectrum
- 5000 lumens
- 8-pack
These 45.75-inch T5HO tubes are designed for compatible 54W fixtures. AgroMax describes the 3000K spectrum as a bloom lamp.
Pros
- Eight bulbs per pack
- 5000-lumen output
- Specified for 54W T5HO fixtures
Cons
- Check the fixture's required length and wattage
- Bloom spectrum may not suit every growing stage
AgroMax’s 45.75-inch tube is a 54W T5HO lamp labeled for bloom with a 3000K spectrum. It is intended for T5HO fixtures that require 54W linear tubes, so confirm both details before replacing a lamp.
The eight-pack can suit a grow setup with multiple matching sockets. AgroMax gives a 5000-lumen output and an extended rated lifespan of more than 20,000 hours.
Choose this warmer spectrum if it fits your growing plan. For a cooler AgroMax option, the 6400K four-pack below is labeled for vegetative and full-cycle growth.
LightWise LWF54T5HO865 8pack 4 FT 6500K T5: Best for a multi-bulb veg setup
- 54W fluorescent
- 6500K
- 5000 lumens
- 8-pack
A pack of eight 45.12-inch, 54W T5 tubes with 6500K cool-white light. Confirm that this length and T5HO format match your fixture.
Pros
- Eight bulbs per pack
- 5000 lumens per bulb
- 6500K color temperature
Cons
- Fixture fit must be confirmed
- Fluorescent rather than LED
LightWise combines a 6500K color temperature with a 54W rating and 5000 lumens per tube. Its eight-pack is a fit to consider when you need multiple T5HO replacements with cool-white light.
The bulbs measure 45.12 inches, so compare that length with your old tube. Confirm the base and fixture requirements as well, since nominal “4 FT” wording alone is not enough to confirm fit.
AgroMax 4-Pack 4 Foot: Best for a smaller T5HO grow pack
- 54W fluorescent
- 6400K grow spectrum
- 5000 lumens
- 4-pack
These 45.75-inch tubes fit compatible four-foot T5HO fixtures that require 54W lamps. The four-pack is a smaller quantity than the eight-bulb options.
Pros
- 6400K vegetative grow spectrum
- 5000-lumen output
- Fixture type and wattage are specified
Cons
- Only for compatible T5HO fixtures
- Four bulbs per pack
This AgroMax four-pack has a 6400K grow spectrum, a 54W rating and 5000 lumens per tube. AgroMax describes the spectrum as suited to vegetative growth, cloning and seed starting.
Its 45.75-inch length and mini bi-pin G5 base make fixture compatibility central to the choice. AgroMax specifies use in four-foot T5HO fixtures only.
The smaller pack may work when you need fewer replacements than an eight-pack. Read our roundup of best 4 foot grow lights if you’re comparing complete fixtures rather than replacement tubes.
Arikit SunBESTer 4FT 54W T5 HO 6500K: Best for 6500K T5 tubes in a five-pack
- 54W fluorescent
- 6500K
- 5-pack
This five-pack offers 54W T5HO fluorescent tubes with a 6500K color temperature. Confirm the exact tube length and base against your fixture before ordering.
Pros
- 6500K color temperature
- 54W rating
- Five tubes per pack
Cons
- Exact replacement dimensions need checking
- Fluorescent rather than LED
Arikit’s SunBESTer tubes are labeled 54W, T5HO and 6500K, with five tubes in a pack. That combination may suit a grower looking for cool daylight fluorescent tubes in a compatible four-foot fixture.
The exact length and base are important here. Check the old bulb and fixture label against the tube before buying, especially if you’re replacing a different brand or model.
Konideke F32T8/841 32W 48 Inch T8 Fluorescent: Best for general T8 fluorescent replacement
- 32W fluorescent
- 4100K
- 2850 lumens
- 10-pack
A 48-inch T8 fluorescent tube with a G13 base and 4100K cool-white light. It is a general T8 replacement, so confirm that your fixture is not designed for T5HO grow tubes.
Pros
- 48-inch length
- G13 medium bi-pin base
- Ten bulbs per pack
Cons
- General fluorescent tube, not a dedicated grow lamp
- Not an LED replacement
Konideke’s 48-inch T8 fluorescent tube is a general-purpose replacement, not a dedicated grow lamp. It uses 32W, a G13 medium bi-pin base and a 4100K cool-white color temperature.
The ten-pack may fit a multi-lamp T8 fixture that calls for this tube type. Its 2850-lumen output is stated for general lighting, so consider a purpose-built grow lamp when plant lighting is your main goal.
How do you match a replacement tube to your fixture?
Match the lamp code, tube length, base and wattage printed on the old bulb or fixture label. Then verify ballast and wiring requirements if you’re changing from fluorescent to LED.
Start by identifying the lamp family. T5, T8 and T12 tubes have different diameters and fittings, so “four foot” by itself doesn’t establish compatibility.
Next, compare actual length. Grow-oriented T5HO tubes in this group measure about 45 to 46 inches, while the Konideke T8 is 48 inches long.
Finally, check the base and power setup. T5HO bulbs commonly use a mini bi-pin base, while the T8 tubes listed here use a G13 base; LED T8 tubes can also require a compatible ballast or rewiring for bypass operation.
Should you choose T5 fluorescent or T8 LED bulbs?
Choose T5 fluorescent when your grow fixture requires T5HO tubes and you want a purpose-made grow spectrum. Choose T8 LED tubes only for compatible T8 fixtures and when their installation method suits your ballast and sockets.
The T5HO options here include 3000K bloom lamps and 6400K or 6500K grow lamps. These are fluorescent tubes designed for plant lighting, with several choices rated at 5000 lumens.
The T8 LED options are general fluorescent replacements. For complete plant-lighting setups, compare LED grow light kits.
They offer 5000K or 6000K light and support different installation modes, but the supplied product details do not position them as horticultural grow bulbs.
For a wider look at bulb types, read Best Grow Light Bulb. Compare the technology and fixture requirements before switching from fluorescent to LED.
Is a 6500K or 3000K tube better for plants?
A 6500K tube gives a cooler color, while a 3000K tube gives a warmer color. Some makers describe their 6500K tubes as grow or vegetative lamps and the AgroMax 3000K tube as a bloom spectrum.
Think about the plants and stage you want to support, then compare the fixture’s required tube type. Color temperature is only one factor, so also consider the bulb’s stated output and how close the fixture sits to the plants.
A mixed setup can provide more than one color temperature if the fixture and growing plan allow it. Keep the lamp types and wattages compatible with the fixture.
How we chose these four foot bulbs
We compared the available bulb specifications against common replacement decisions: tube length, lamp technology, wattage, color temperature, base and pack size. The order reflects fit and usefulness for the search, with compatible T5HO grow lamps ranked ahead of general T8 replacement tubes.
Our score weighs specs, features and buyer feedback against what you’re shopping for. We did not test these bulbs in a grow fixture, so confirm compatibility with the fixture maker’s instructions before replacing or rewiring a lamp.
Which four foot grow light bulb should you choose?
Choose the VIVOSUN T5 Grow Light Bulbs 4Ft for a compatible 54W T5HO fixture and 6500K fluorescent light. Pick an AgroMax tube for a stated bloom or vegetative spectrum, or a T8 LED only when your fixture supports that format and installation method.
Our top 3 picks at a glance
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1
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2
Best for matching shorter T5 fixtures
VIVOSUN T5 Grow Light Bulbs 2Ft
9.6/10 our score
See it on Amazon -
3
Frequently asked questions
Are all four-foot grow light bulbs the same length?
No. A four-foot label can refer to a nominal fixture size, while the tube itself may measure about 45 to 46 inches or a full 48 inches.
Check the old lamp's printed code and measure it, then compare the replacement's length and base before buying.
A close nominal size does not guarantee that the tube fits.
Can I put an LED T8 tube in a T5 grow light fixture?
No, a T8 tube is not a direct replacement for a T5 tube. T5 and T8 lamps use different diameters and bases, and fixtures may also differ in ballast or wiring requirements.
Match the replacement to the fixture label and follow its wiring instructions.
If a ballast bypass is needed, use a qualified electrician.
What does T5HO mean on a grow bulb?
T5HO means a high-output T5 fluorescent tube. Many four-foot T5HO grow tubes are around 45 to 46 inches and use 54W, but confirm the exact length, base and wattage your fixture requires.
A standard T5 tube or T8 tube is not automatically compatible.
Is 6500K or 3000K better for grow light bulbs?
A 6500K tube gives a cooler, blue-leaning light, while a 3000K tube gives a warmer light. Some grow lamp makers label 6500K tubes for vegetative growth and 3000K tubes for bloom.
Choose by your plants' growth stage and the fixture's needs.
Color temperature alone does not tell you how much usable light reaches the leaves.
