Grow light panel vs bulb vs bar: which to buy for seedlings

Every grow light worth buying now is LED, so the old fluorescent-versus-LED debate is settled: LEDs run cooler, last far longer, and sip power. What actually decides your purchase is the shape of the light and how much of your growing area it needs to cover. A panel, a bar, and a bulb are three answers to "how many plants am I lighting, and where." Match the form factor to that and the brand matters less.

Good light is what stands between you and leggy, stretched seedlings on a windowsill. If you are starting seeds indoors, pair whichever light you choose with the right timing from the planting calendar so transplants are ready for your last frost. For the plants themselves, our tomato and basil profiles cover what strong early light sets up.

Panels: even coverage for a shelf of plants

A panel is a flat array of diodes that casts a broad, even spread of light over an area, typically a couple of square feet at seedling height. It is the most flexible form factor: it takes seedlings from sprout to transplant, then keeps going for herbs, leafy greens, or a small flowering plant. You hang it from a shelf or frame and raise it as plants grow.

The Spider Farmer SF-1000 is the pick because it pairs a genuinely full spectrum with an efficient driver and a dimmer, so you can run it soft over tender seedlings and turn it up as plants demand more. It covers roughly a 2x2 foot area for seed starting and runs cool and quiet since it is fanless. Owners consistently report tight, stocky seedlings rather than stretched ones, which is the whole point of a good panel. You can check the SF-1000's current price before deciding.

The Mars Hydro TS 1000 delivers very similar coverage and a full spectrum for less money, which makes it the value panel. It is also dimmable and fanless, and it hits the same roughly 2x2 foot seed-starting footprint. The trade-off against the Spider Farmer is usually finish and driver quality at the margins, but for most home seed-starting setups the difference is small and the savings are real. You can compare the TS 1000's current price against the overall pick.

Bars: the most efficient way to light one flat

A bar (or strip) light is a long, thin fixture you hang just a few inches above a single tray. Because it sits so close and spreads light along a line rather than a cone, it puts nearly all its output onto the plants with very little waste, which makes it the most efficient choice for lighting one flat of seedlings on a shelf.

The Barrina T5 pick is a six-pack of linkable 4-foot bars, so you can lay out exactly as much light as your shelf needs and daisy-chain them from one plug. Hung a few inches over a standard 1020 tray, they blanket seedlings in even light with no hot spots and almost no stretch. They run cool enough to sit close, and the linkable design scales cleanly across a whole shelving unit. The honest limit is intensity: bars are ideal for seedlings and leafy greens but do not push the deeper penetration a panel gives fruiting plants. You can check the Barrina T5 six-pack's current price if a full shelf of seed flats is your setup.

Bulbs: one lamp, one or two plants, least money

A grow-light bulb screws into a standard socket, so it turns a desk lamp or a clamp fixture you already own into a grow light. It is the lowest-cost, lowest-commitment option and it is genuinely useful for one or two houseplants, a single herb pot, or a couple of seedlings on a windowsill. What it is not is a way to light a whole shelf.

The SANSI full-spectrum bulb puts out a surprising amount of usable light for a screw-in, with a broad spectrum and a built-in ceramic heat sink that keeps it cool and long-lived. Drop it into any lamp aimed at a plant or two and you have effective supplemental light for pennies of hardware. It is the pick when your need is small and specific rather than a full seed-starting station.

The GE Grow LED BR30 is a flood-shaped bulb with a balanced spectrum designed to look pleasant in a living space, not just perform in a grow tent. That makes it the pick for lighting a houseplant somewhere you actually live, where a magenta panel would be an eyesore. Coverage is still one-plant scale, so treat it, like any bulb, as a spot solution rather than a shelf solution.

How to choose between panel, bar, and bulb

It comes down to how many plants you are lighting and where.

Coverage area. A bulb lights one or two plants. A bar lights one flat or shelf. A panel lights a couple of square feet and pushes more intensity for demanding plants. Count your plants first and buy the smallest form factor that covers them.

Efficiency and cost of running. All three are LED and cheap to run, but a bar is the most efficient per plant because it sits so close with so little waste. A panel draws more but does more. A bulb is the cheapest hardware but the least efficient use of light per watt for anything beyond a plant or two.

Fit with what you own. A bulb needs nothing but a lamp you already have. A bar and a panel both need a shelf, a frame, or hooks to hang from and some way to raise them as plants grow.

What you are growing. For seed starting and leafy greens, a bar or panel is ideal. For pushing a fruiting plant like a pepper or a compact tomato indoors, a panel's intensity matters. For a windowsill herb or a houseplant, a bulb is plenty.

Frequently asked questions

Is a grow light panel or a bulb better for seedlings?

For more than a plant or two, a panel or a bar is better because it covers a whole tray or shelf with even light, which is what keeps seedlings stocky instead of stretched. A bulb is fine for one or two plants on a windowsill but cannot light a full seed-starting flat evenly. Match the form factor to how many seedlings you are starting.

Are LED grow lights better than fluorescent?

Yes, for almost every home grower. LEDs run cooler, last far longer, use less electricity, and now cover the full spectrum plants need. Fluorescent tubes still work, but they burn out sooner, run hotter, and cost more to operate. Every pick here is LED for those reasons.

How close should a grow light be to seedlings?

Close. For bar and strip lights, roughly 2 to 4 inches above the seedling tops; for a bright panel, a bit higher per the maker's guidance. Then raise the light as the plants grow to keep that gap. Light hung too far away is the single most common cause of leggy, stretched seedlings.

How many hours a day should I run a grow light?

Most seedlings and leafy greens do well with 14 to 16 hours of light a day, then a dark rest period. Put the light on an inexpensive outlet timer so it is consistent. More is not better past that range; plants need the dark period, and constant light wastes electricity without improving growth.

The bottom line

Buy a panel when you are lighting a shelf and want intensity that carries seedlings through to fruiting plants: the Spider Farmer SF-1000 overall, the Mars Hydro TS 1000 for value. Choose a bar like the Barrina T5 six-pack when you want the most efficient, even light over trays of seed flats. Reach for a bulb, the SANSI or the GE Grow BR30, when you just need to light one or two plants with a lamp you already own. Then keep it close, run it on a timer, and time your seed starting with the planting calendar.