Thanks for all the great grow articles; I’ve learned so much about marijuana from HIGH TIMES over the years! I am wondering if it is too late for me to grow a plant or two outside this summer and get a harvest come Autumn? I have a back deck that gets sunlight most of the day. We live in Tennessee. I started some bag seed, and the seedlings are nearly six inches in height now. What should I do?
Wow, great question and good timing, Zach!
It is not too late to grow out a few plants outdoors for the summer/fall cycle, though you are cutting it pretty close. Ideally, you want to get plants outdoors by April or May. But right now, even if you live in the latitude of North America stretching from New York to San Francisco, you are still receiving just over 14 hours of daylight, and you have almost seven weeks before that drops below the all-important threshold of 12 hours daylight. In Tennessee, you might even have an extra week or two being further south, so let’s get started right away.
Cannabis Flowering & Photoperiod
It is important to remember that cannabis plants respond to photoperiodism, which is the change in length of light and dark cycles within a 24-hour period. This shift signals cannabis plants to begin flowering once the photoperiod (light) drops to 12 hours or less.
Cannabis plants of any size or age will begin to flower once the photoperiod goes to 12 hours of light or less in a 24-hour day. While this is quite handy that a grower only needs to sit back and let the plant start fruiting, there is a responsibility of the grower to ensure the plants are mature and developed enough to handle this phase of growth. A very young seedling or clone will not fair as well in flowering as an older, more advanced plant.
As a general rule, the minimum time to vegetate a seedling or clone is usually two weeks, with most growers preferring to “veg” for around four weeks before inducing flowering by changing the photoperiod to 12/12. Still, at 6” tall and having a few leaf sets, the plant described by Zachary above can be set outside now, as it will likely continue to grow (veg) for a few weeks before it starts to flower, assuming that it can be kept in total direct sunlight for most of the day.
New growers become concerned when their outdoor plants begin to flower before the daylight hours drop to 12 hours per day. There is no need to worry as this is perfectly normal. Unless a cannabis plant is getting more than 12 hours of direct light, its internal physiological responses will register a change in photoperiod, even if the sun is out and bright, but the plant remains slightly shaded.
In reality, it is quite tough to ensure your plants are getting direct sunlight for 12+ hours a day to stay in a vegetative state—especially if we are talking about a backyard deck or patio versus plants in an open field. (This is why many outdoor/greenhouse growers deploy supplemental lighting.)
So, in Zachary’s example above, placing his plant outdoors in direct sunlight will likely only keep the plant in a veg state for a couple more weeks before the plant begins to flower, even though our sunrise/sunset charts are telling us there are more than 12 hours of daylight in the coming weeks.
Working in Zach’s favor is the fact that he has already begun growing his plants (presumably indoors), which many outdoor farmers do earlier in the year when they are waiting for the ground to thaw out. Starting a few seeds or clones indoors under simple and inexpensive fluorescent lamps for a few weeks is always a good idea before moving them outdoors. You could even hang this lamp outside on the deck above the plants and, using a timer, have the lamp go on around 4 – 5 p.m., when the sun gets lower in the sky.
Ideally, you want to get your plants outdoors before June to allow for ample “veg” time, but even this late in the season, you can salvage a few outdoor plants and get some decent buds, even if the yield will be lower than if the plants had a full season under their belts.
Cannabis plants, on average flower for eight weeks. Some finish earlier while others, like sativas, can take up to 10 or more weeks. So if you’re thinking about throwing some bag seed out there, best to do it now and look for a quick-finishing indica that you can cut down in early October before the frost comes.
Thanks for reading everyone and remember: Grow… And help the world grow, too!