should i keep it under light 24 /7 till it gets tiller then cut back the light ???

If its auto u can run it 24/7from start to finish

Plants create food for themselves with light through photosynthesis. Plants use food/energy to grow during dark periods. All plants need rest or dark period to grow properly. HerbalEdu said it spot on.. by the way, you should consider transplanting your plant into a container that is not clear. Roots do not do well with light.

You're only using a 9W?? That's going to be pretty weak for the plant ... but I grow ALL my autoflowers under 24/7 lights from seedling to harvest with no ill effects. Lots of people disagree with me but none of my autos have EVER had any adverse reaction to not getting any "rest" ... I would consider stronger lights for this grow, though... especially as it gets to the flowering stage... Good luck

more is not always better... the right amount is what we want with most things related to growing a plant well. maturity of plant impacts how much light per day it can handle... you'll prolly have to increase light over next couple weeks to avoid stretching... observe and react. how many hours per day is as much about the intensity of the light you own as anything else. REad up on DLI... daily light integeral. it is a way to compare apples to apples regardless of garden size. early on, you may only want 20-25 DLI, but by the time it is mature vege plant, you can go up to 40-ish DLI. DLI is simply X number of photons hitting the plant per day... it is broken down incrementally so that garden size (area) and hours of use (time) is irrelevant when comparing DLI values (*common sense applied... obviously some few hours with super intense light will only burn the shit out of the plant or maybe light it on fire if the time frame is short enough but still providing same number of photons, lol.) how much a plant can handle per day is relative to temperature and atmospheric co2. if you increase co2 to 1300ppm and tightly control temperature and RH to maximize resulting plant metabolism, then you can push up to 50+ DLI. Maybe 55 DLI? You can give 25% to 33% more light per day in this context compared to atmospheric co2 and only loosely controlling temps/rh. you will get 25-33% more yield, too. you can do the math on this stuff, but just knowing the concepts can help too. Regardless, some amount of trial and error is needed as these are merely ballpark targets. environments vary greatly and that will impact what you can provide in a given day... each garden can be a bit different in regard to "max" DLI because of this fluctuation. So, simply read the plant... watch resulting internode length.... if too long, needs more light. if too tight, needs less light. take some notes for early vege and mature vege.. and some idea of how it ramped up... this will make it easy-peasy the next time and if consistent each time it'll become habit in no time. if you ever see "too tight" in mature vege, you know you are capable of providing more photons than it can handle because it is having an negative impact on the plant. as you adjust and find a zone where the plant is super healthy, yu can feel confident you are providing as much light as you can given the context of your garden at that time. as long as you provide more than 21-23 DLI (give or take) you should grow at least decent buds --- this is strictly about density of the buds, not the qualtiy which is mostly genetics. yield will increase with more light. you'll get less airy nugs with more light... it won't improve quality/potency much, unless comparing to a context providing way too little light.

plants do need a rest period for a properly functionning metabolism google "circadian rythm in plant lifecycle" for more details either go 20/4 18/6 or 16/8

Plants need rest. I would go 20/4 max, and that's if I didn't care about electrical cost. 18/6 is the standard since 20/4 shows little to no difference in growth.

High Bigjohn78, I would go for 18/6 light schedule. I did a test one time with autoflowers (White Diesel Haze from White Label). Left 3 plants on 24 hours, 3 on 20/4 and 3 on 18/6 and all 3 tents had same setup. The 24 hours tent was 1 week earlier with harvest but had smaller yield. The 20/4 and the 18/6 were almost equal with harvest time and yield. So it is not worth the 2 extra hours electricity in my opinion. I never tried to compare autoflowers on 24 hours or 20/4 light scedule during vegging and 18/6 during flowering compare to 18/6 for the whole grow. But because the 24 hours had lower yield and the 20/4 and 18/6 are almost identical at the end I do not think that you will gain from doing so. Happy Growing!

Do not use 24 hour light. I would go 18 hours on, 6 hours dark.

That's one way you can do it, for sure. But, don't forget, plants are living too. And all living things need rest. Once I went with an 18/6 cycle instead of lights for 24 hours straight, I haven't looked back and my plants greatly appreciate it. Good luck!