ScrOG Time-Lapse Video & Grow Journal
It’s still drying so stay tuned for the final yield. My last run was 36 ounces.
More About Setup: Rockwool, six plants, 1000W HPS, Pureblend Pro and a few CANNA products, and of course CO2.
The plant roots are sitting in rockwool slabs in an ebb & flow tray that contain the entire rootmass. During normal growth they get submerged in 5 gallons of pH balanced nutrient solution every day. See picture
Learn more about this cannabis grow journal below!
Getting started: Clones
I keep clones in temporarily in an ebb & flow tray so I just top feed and it drains into a bucket.
I start from clones for this grow, and the official veg time starts after they were rooted. The rooted cuts were taken from the aeroponic cloner and placed under fluorescent lights for two weeks before going in the big tray under the HPS light. Then they vegged for another four weeks before changing to flower.
All the plants are grown hydro, in rockwool. You can see the slabs here.
I use an ebb & flow tray for flowering as well which can be used with a reservoir and pumps in a recirculating setup or drain to waste.
The plant roots are sitting in rockwool slabs located in an ebb & flow tray that contain the entire rootmass. During normal growth they get submerged in 5 gallons of pH balanced nutrient solution every day.
Training & ScrOG Maintenance
I’ve never FIM’d really but did some topping very early on in the grow. I topped the plants in weeks two and three of veg and not much after that, just enough to get the auxins spreading around and starting out the bush shape.
Once they reach the net I do a lot more LSTing (low stress training) within the net to keep them trained.
As they get taller and flowers start to form I’ll ‘cross’ train them where I take two nearby colas oriented parallel to each other like | | and cross them using their flower nodes to hold them in place like X which reduces their overall height and helps me even everything out. I also do defoliation on the center of the SCROG closest to the light.
Maintaining the SCROG requires the most work during the last week of veg and the first 4-5 weeks of flower, which usually amounts to 90-120 minutes a day at the beginning of their light cycle. For the remainder of the grow the tending and maintenance times are minimal.
Here’s a time-lapse moving gif showing what tending the ScrOG looks like
There’s six plants there, though since they’re all identical genetics I like to think of them as one big plant.
I tied some twine around the outside to bring all of the outer perimeter colas inwards and create the ‘bowl’ shape I typically aim for with my SCROGs.
Should I use CO2 for my grow to get results like yours?
CO2 enrichment is like putting nitrous oxide boosters in a car, it only makes sense when every other aspect of your performance is tuned and can handle the enrichment. You wouldn’t add NOS to a Ford Pinto because it wouldn’t make a difference and at best would be a waste of money and at worse it could cause problems elsewhere.
Growing marijuana, like many other plants, has to do with the Law of the Minimum which is evident in the statement, “The availability of the most abundant nutrient in the soil is only as good as the availability of the least abundant nutrient in the soil.”
The basic building blocks for your plants are Nutrients, Water, Light, and CO2. At any given moment one of these is the ‘minimum’ (or the scarcest) and creates a bottleneck of resources for everything else. In your case that minimum is the lighting, since that is your least abundant resource. You can give the plants all the CO2 and water and nutrients you want but since your light is the limiting factor all of the increases in everything else will be for naught and can even be harmful.
That’s why you shouldn’t use CO2 with fluorescent lights. CO2 only makes sense when every other aspect of your grow environment can handle it. Once you have HID discharge lighting and your nutrients and watering schedules are dialed in, CO2 will be your ‘minimum’ and your limiting factor for growth, which is the point at which you should start considering adding CO2 to your grow. Until then you’d be wasting your resources.
How do you flush your plants in a ScrOG setup?
I start the flush process 10 days before harvest. Every day I fill up four 5-gallon buckets with unbalanced tap water, and submerge the rockwool slabs for a few minutes with each of the 5-gallon buckets. This pulls the salts out of the rockwool. Over the course of the 10 days, 200 gallons of water goes through the slabs.
I measure the TDS/EC of last bucket of runoff every day and the PPM falls exponentially. The first day of flush the fourth bucket TDS measures
1400 ppm. By the last day of flush the TDS measures around
140 ppm, which is within 50 ppm of the tap water I start with.
The measuring allows me to be sure that I’ve flushed as many salts as possible out of the medium. I use unbalanced tap water to flush because in my opinion, any nutrients the plants are consuming at this point come from within the plant’s reserves and should not be coming from the medium. Because of this, the pH of the water is irrelevant since pH only matters when you’re trying to maximize nutrient uptake which is the opposite of what we want during flush.
I also pull off many of the fan leaves when I start flush to encourage the plant to pull nutrients from the leaves nestled around and within the buds to further improve quality.
It’s still drying so stay tuned for the final yield. My last run was 36 ounces!
How long should I leave my grow lights on for?
Some gardeners like to leave their lights on for 24 hours to get maximum growth. However, by far the most popular light duration for vegetative plants is 18 hours on and 6 hours off. This schedule will mimic a day of full sunshine followed by a natural dark period. Using this method will save the gardener electricity while still providing exceptional growth.
Some plants are triggered to flower by a reduced duration of daylight. These plants can be tricked indoors into producing their flowers with a reduction of light duration. To achieve this, most gardeners will reduce their light to 12 hours on and 12 hours off. Other plants simply flower then they are mature and can benefit from the 18 hours of light throughout their life.