These are the spiral bulbs that you see in most households, though those are way too low in wattage to use. They are best suited for seedlings and the veg period but can be used for the entire grow. You’ll need to have a lot however for flowering, but many growers use CFLs. I used them as my sole lights for my first few years and was able to always produce enough bud for both myself and another.
You’ll need a minimum of 200 watts, which is several lights, and make sure you calculate the actual wattage and not the equivalent wattage. You can also buy CFLs with different light spectrums/temperature, which is great for mixing and matching.
Easily the cheapest startup cost and most CFLs will last for multiple grows.
Height: The lights need to be right up on the plant for maximum light penetration. Seedlings can be several inches away from the bulbs, but from veg and after you want the lights around 1” to 2” inches away. My general rule is to take your hand and place it next to the bulb, if you can hold it comfortably next to the lights for 30 seconds then your plants will be fine being that close.
Stealth: Nothing suspicious about CFLs if someone finds them or sees you buying them.
Heat: CFLs are the best if you need low heat and want to keep your electric bill low. However, in my opinion, if you want to actually grow a decent yield, you will have enough CFLs running that you will need something to keep too much heat from building up. A decent fan can easily circulate the air enough to keep stagnant hot air from building up.
Lowest yield: Like I said above, I was able to grow enough marijuana with one plant at a time to sustain two people who used every day. However, we saved a lot of marijuana by mostly vaping it instead of combusting. If we smoked every day, we would have most likely would’ve ran out of marijuana before the next grow was done.
Heat: Since you want to get your plants right next to the lights, you’ll still need a heat exhaust system setup. A few small fans will do the trick.
Daily maintenance: Cannabis puts on height decently fast until it reaches flowering and since you want your lights right up on the plants, you’ll have to keep adjusting. This becomes a decent amount of work in pre-flowering when plants can double their height in just a few weeks. Personally, I create a pulley system that allowed me to easily lower my plant when it got too close to the lights. Even then I had some grows where I accidentally burned a leaf or two because I didn’t get to the plant fast enough.
You can buy a 4 pack of 23 watt CFL light bulbs on Amazon for around $10. So for $30 smackeroos, you can have 276 watts across 12 bulbs. That’s a lot of bulbs but you can also find larger CFLs that are 40 and even 80 watts. Definitely the cheapest initial bulb setup, and in my experience, they lasted a really long time and through several grows.
If you can afford to spend more and can allow for a little more height, check out T5 Fluorescents.