Make sure to get a light socket for each CFL bulb! This is what you use to get light to your bulbs from the wall.
This will help you estimate how much yields to expect from your CFL grow, but you need to remember to take this with a grain of salt. A very general rule of thumb is to expect about 0.25g/watt of CFL light if you use plant training and don’t run into major plant problems. This is counting CFL true watts, not any type of “equivalent” watts. Some CFL growers definitely get bigger yields than that with CFLs, up to about 0.5g/watt for the pros, but 0.25g/watt is what you should expect as an upper limit for a first-time cannabis grower.
The size and shape of your plant is going to have the biggest effect on both your cannabis yields and how many CFLs you’ll need. That’s why no “formula” is going to be accurate all the time; marijuana plant training makes such a big difference on your final yields and its impossible to know what a grower’s skills will be. That means any formula is just a rough estimate, but if you follow the steps in this CFL growing tutorial you’ll produce great results every time so you get the cannabis CFL yields you expect, or even more!
What has a greater effect on your results is how much light (wattage) in total. More light/wattage is better with CFLs. For example, I’d rather have 150W of 5500k bulbs than 100W of 2700k bulbs for flowering. The increased light intensity will help your yields more than getting the exact right color spectrum.
In order to switch to the flowering stage you need to switch your CFLs to a 12/12 light schedule using a timer. This means that the plants should get 12 hours of light and 12 hours of dark each day. It’s really important to make sure the plant doesn’t get any light during the dark period. Light leaks cause problems! Your grow space needs to be completely light proof in the flowering stage.
As a bonus to doubling up, setting up more than one bulb per socket can often be cheaper than buying an individual light socket for each light, especially if you buy online. It also is really convenient for arranging CFL bulbs around your plant.
Note: sometimes either bulb is listed as “40 watt” or “42 watt”
To get the biggest yields, keep your CFLs as close to your buds as possible (without burning them!)
What Color CFLs Should I Get? (CFLs and Light Spectrum)
As the plants get taller and start blooming, you may need to get a couple more CFLs to light them from the sides. Basically if you see any dark or shadowy areas that are more than 6 inches from a CFL, then you should get another CFL to plug in that ‘hole.’
I think it would be safe to assume that even a beginner can expect to get 1-3 ounces of dried buds per plant if you just follow these instructions. Even if you mess up (and you will), you’ll still get at least that if you can get your plants to harvest.
To initiate the flowering stage, you will switch your light schedule so that your lights are on for 12 hours a day, and off for 12 hours a day.
In order to prevent over or under-watering, make sure you water thoroughly every time, and wait to water again until the top inch of coco coir feels dry.
Cons of Growing Marijuana with CFL Grow Lights and Coco Coir
Recommended For: People who want a super-cheap, super-easy grow style.
So, you can see that it doesn’t cost that much to get started growing cannabis with CFLs! After you get going you can expect to spend about $30/month in electricity, supplies, etc. considering an electricity price of When not using nutrients, make sure you still pH your plain water before your feed your marijuana!.12/kWh (average cost of electricity in the US). So, if you harvest in 3.5 months, which is the average time, you’ll have spent about a total of $300 – $360 for your entire first grow, including setup, electricity, nutrients and maintenance. After that you can expect to pay about $100/grow since you won’t have to invest in most of the setup costs again.
It’s optimal to use ‘daylight’ (6500k) colored bulbs for the vegetative stage and ‘soft white’ (2500k) colored bulbs for flowering, but you can use any color CFL during either stage and your plant will grow well. The color spectrum of the bulb is not nearly as important as the total wattage.
Total Startup Cost for One Plant: $201 – $258
Using CFL bulbs allows you to use daylight mimicking CFL bulbs during the vegetative stage of the plant’s life and use a softer light for the flowering cycle. You don’t want to use a soft white CFL for vegging as it is closer to the sunlight in Autumn when plants start to flower. However, if soft white is all you can find, it will still work as long as you have enough wattage to supply ample light to each plant.
CFL Light Bulbs For Growing Weed
To get big, productive buds when using fluorescent light bulbs for growing weed, you need the most light intensity that you can produce. This is the most important factor when flowering with CFL lights.
How To Get Big Buds With CFL
When setting up something like a small CFL closet grow, you might want as little light as possible. Each cannabis plant will require around 80 watts of light, with more being better. Using 2 40 watt CFL bulbs is sufficient for a mini CFL grow.