So a lux meter gave me the tools to get bigger yields by getting more light to my plants. The best part is I didn’t have to change my grow light – I was able to get better performance out of the same lights with different positioning.
And I kept testing lux levels throughout their life!
Using a Lux Meter for Different Types of Grow Lights
The grow shown below was the first time I ever used a lux meter. For this grow I was using a 250W HPS light for the first time. I wasn’t familiar with how far to keep the light away from my plants. Luckily, I had a lux meter to give me definitive answers. I started testing light levels and how they vary with the position of the light distance and the plants.
The amount of light you get from direct sunlight on a bright, sunny day is 40,000 up to about 100,000 lux. At the high end, the sun provides more light than the plant can use. Imagine a cannabis plant in a pot in the desert – the direct sunlight would be too much.
How much lux do you want to deliver to your plants?
Here’s the Lux Meter I use…
You get a freebie here Ferg, after this you’re gonna have to read a grow book.
Marijuana requires 6,000 lumens (at least) per sq/ft. for optimum growth. Watts & lumens are usually printed on each bulb and/or the package they come in.
Flo’s emit 75 lumens per watt, so 4 x 40 x75 =12,000, or enough for 2 sq/ft.
(HPS kicks out 125 lumens per watt).
this is my first grow and im trying to make it to the harvest with this one. i need to know if 2- 4 foot 40W fluorescent wide spectrum lights going to grow 4 plants? or do i need to get some new lights? and also is a grow box that is 4 1/2 foot tall and 2 1/2 foot wide going to fit 4 fully grown plants inside of it?
You can grow marijuana under flo’s, but growth will be slow and you’ll only get 1/3 the yield vs. HPS.
You only gave 2 diminsions of your grow box. If it’s 2.5′ x 2.5′, your only gonna be able to get 2 pot plants in there. Have you ever seen a pot plant?
Good luck getting 4′ flo’s in there.
Apollo Horticulture describes this bulb’s light as “warm and inviting”. It makes a pleasant and effective addition to your grow room.
Another great thing about CFLs is that they can be positioned in innovative ways. Some people place them horizontally, while others dangle them vertically over the plants. Since they can fit into a small space, they’re pretty good for stealth growing.
While fluorescent lighting may work for small-time growers with a handful of plants, you will need to invest in an upgrade if you’re wanting to produce more marijuana. LEDs and HIDs are much better for getting a higher yield.
3. EnviroGro FLT24 2-ft T5 Bulbs
The downsides of CFLs is that they are less efficient than more powerful lights. Furthermore, you may need to keep moving and repositioning the bulbs for best results.
Please note that this bulb is not the best on the market. However, it is cheap and will do the job in the smallest grow tents.
Even stronger is the Apollo Horticulture 25-Watt bulb. This CFL bulb comes with a USA standard reflector and a 13ft power cord, perfect for setting up your grow space. The bulb is 6400K, but the brand recommends switching to a 2700K lamp during the flowering period.
5 Best Fluorescent Lamps for Growers in 2022
Here are WayofLeaf’s top picks for fluorescent grow lamps. These should suit all budgets and grow spaces, no matter what you need.
T5s, meanwhile, get their name from their tube shape and 5/8” diameter. T5 bulbs usually come in a set, where multiple tubes are placed side by side in a panel. As a result of this set-up, T5s provide more even light coverage. You’ll need to hang T5s from a fixture, but don’t worry, as they’re often very cool and won’t cause heat damage.