Grow light burn on leaves: bleaching, crisp edges and what to change
Bleached tops and brown edges under a grow light are not always the light. Read the pattern on the leaf, rule out the look-alikes, then change one thing.
Article archive
Grow Lights article archive
This is the plain utility list for every published grow lights guide. For the main topic page with curated pathways, featured entry points, and broader context, use the primary hub.
Primary topic hub
Grow Lights
Grow lights are often overcomplicated. This hub focuses on the decisions that matter for indoor herbs, seedlings, and compact crop systems: runtime, distance, fixture shape, and signs of plant stress.
34 articles
All published grow lights guides
Browse the full set of published guides in Grow Lights. This archive stays intentionally simple so it does not compete with the main hub.
Grow lights for tomatoes and other fruiting plants indoors
Fruiting plants are the heaviest light users on an indoor shelf. Extension figures for full-sun plants and a strawberry trial show how much more than herbs, and why hours alone will not close the gap.
DLI calculator: convert PPFD and hours into daily light integral
Daily light integral is PPFD multiplied by the hours a light runs, converted from a per-second rate into a per-day total. Enter both below to get the number, then check it against a target.
DLI targets for herbs and leafy greens: what to aim for
A single DLI number does not fit every herb. Here is the general target for leafy greens, and what published research on basil, sage, and mint actually measured.
Grow light coverage area: how to measure yours instead of guessing
There is no watts-per-area figure that describes how far a grow light's coverage reaches. Measure your own shelf with a PAR grid, then turn that reading into a footprint number you can trust.
Grow light heat management: what actually matters on a shelf
A warm top shelf is not just a comfort problem. It changes the light your herbs want and wears the fixture down faster, and the fix is usually smaller than a fan.
Grow light safety: what actually needs attention
A grow light is not dangerous equipment. But it does put a driver, a timer and a power strip in the one room where you deliberately add water — and that combination deserves five real minutes of attention.
Grow light mistakes that stress herbs more than they help
Most grow light problems trace back to a handful of repeatable mistakes, not a mysterious plant failure — and most of them show up as a visible sign you can check today.
Grow light schedule planner: hours by plant and season
Pick a growth stage and how bright the room already is, and the planner below returns a recommended runtime, the matching on and off times, and the dark period that goes with it.
Grow light spectrum explained: what actually matters for herbs
Full spectrum, blurple, enhanced red — the labels change every season, but for herbs the answer is simpler than any of them.
How many watts does a grow light need?
Wattage alone does not predict how much light reaches a plant, and an equivalent-wattage claim predicts even less. Here is the arithmetic that gets closer to a real answer.
Grow lights for seedlings: the complete setup
A tray of seedlings under lights needs more than a bulb overhead. It needs the right kind of fixture, a photoperiod on a timer, and a distance that changes every week as the seedlings grow.
Grow lights vs sunlight: what actually decides the comparison
Sunlight and a fixture are not competing technologies. They are two ways of delivering the same thing, and the comparison runs on three axes.
Growing herbs in winter: why grow lights become necessary
The same windowsill that carried a plant in June often cannot carry one in December. That is a delivery problem, and a grow light is usually the smallest fix for it.
How long do LED grow lights actually last?
An LED that still turns on is not necessarily still doing its job. Here is the arithmetic behind L70, and how to catch a fixture that is quietly falling behind.
Turning a glass display cabinet into a grow shelf
The appeal is obvious: a clean glass front instead of exposed pots and cords. What is less obvious is that sealing plants behind glass changes the air around them as much as any light you add.
Lighting a four-tier herb rack: a systems approach
Light one shelf and you are done. Light four stacked shelves and the decisions start talking to each other: heat moves upward, height budgets shrink, and one crop's best tier is another crop's worst.
Lux to PPFD: what a light meter reading actually tells your plants
Lux measures what a human eye sees; PPFD measures what a plant can use. The gap between the two explains why a bright reading does not guarantee strong growth.
One grow light or several: how to decide
There is no fixed ratio of lights to shelf feet. The count follows from your plants' footprint and their light target, and it changes depending on whether they sit in a row or a cluster.
Do reflective materials actually help a grow light shelf?
Foil, mylar, and white paint can return some of the light that would otherwise land on a wall. Whether that is worth doing depends more on your shelf than on the material.
Can regular LED bulbs grow plants? Yes, if they're close and on long enough
A straight answer for anyone eyeing the bulb already in a lamp: the spectrum is usually fine, and intensity plus daily run time are what actually decide whether it will grow something.
Grow tents for herbs: what they actually solve
A sealed tent solves problems most herb growers don't have, and creates one they do: heat. Here's when the enclosure earns its place anyway.
Grow light electricity cost: calculate the real monthly bill
The monthly cost of a grow light is a four-input calculation. Measure wall power when possible, then compare cost per useful growing area—not labels alone.
PPFD and DLI for indoor herbs: a practical measuring guide
PPFD is a snapshot; DLI is the daily total. Used together, they turn grow-light setup from a distance rule into a measurable map.
Best grow light timers (buyer's guide)
Consistency is everything in indoor horticulture. If you forget to turn your grow lights on, your plants will starve. If you leave them on too long, your greens will stress and bolt. Automating your photoperiod with a reliable outlet timer is the single easiest upgrade you can make. Here are our top picks.
Best clip-on grow lights for herbs (buyer's guide)
You do not need to install massive ceiling-mounted grow panels or ugly industrial fixtures to keep your indoor herbs alive. With a flexible, clip-on gooseneck LED grow light, you can clamp a soft, full-spectrum light source directly onto your desk or windowsill in seconds. Here are our top-rated options.
How to grow herbs indoors under a grow light
A grow light lets you grow herbs indoors anywhere, even with no sun. Here is the simple end-to-end setup: which light, how high, how long, and how to avoid leggy growth.
Best grow lights for apartments and windowsills
Apartments need grow lights that fit a small space and look acceptable in a living room. Here are the best compact LED types and what to check before buying.
LED vs. fluorescent grow lights for herbs: which is better?
Fluorescent tubes used to be the gold standard for indoor gardeners, but modern LEDs have changed the game. Find out which technology is right for your space and budget.
Best grow lights for herbs: what actually matters before you buy
Most indoor herbs don't need a massive, expensive grow tent light. Here is how to choose the right LED bulbs, strips, or halos for your real apartment setup.
Can herbs grow indoors without direct sunlight? Yes, but bright windows matter
A realistic answer to a common indoor-herb question, with clear expectations for growth, herb choice, and when a grow light becomes the cleaner solution.
How much light do herbs need? 6+ hours of sun
A practical guide to how much light herbs need, including a quick answer for direct sun, indoor windows, and grow light setups that actually support growth.
How many hours should grow lights run for herbs? 12-16
Most herb grow lights should run about 12 to 16 hours per day, but intensity, distance, and a stable dark period matter as much as the timer itself.
Grow light distance for seedlings: how close is too close?
Seedlings usually need grow lights much closer than beginners expect, but the exact distance depends on fixture strength, lens design, and plant response.