Combining the Sun with Indoor/Greenhouse

Hi all, this post may be somewhat lengthy, as it delves quite deep into my issue, and it may also take a paragraph or two to explain exactly what I’m doing and inquiring about.

I am Growing in South Africa at roughly 25-26 deg latitude. I am obviously in the Southern hemisphere, but I assume the same principles will apply at 25-26 deg latitude in the Northern hemisphere?

I have a Greenhouse of about 3m x 4m. It has full exposure, no shadows cast on in from trees or nearby buildings. I have grown two years in a row thus far. The first time being guided by an expert in the field. The second year I did mostly on my own, consulting some experts to whom I had access from time-to-time. Yet, the original expert, and the two whom I consulted the second year, have, quite by coincidence, all relocated, leaving me all by my lonesome :slight_smile:

During these two years I obviously grew light-cycle crops, but at various times I attempted Autoflowers as well. Upon initially starting up my adventure, I had intended to ONLY grow Autos, as I did precisely NOT want to navigate the light-cycle path. Yet, my experience of Autos has been that the seeds end up costing almost a quarter (sometimes more) of the actual return. This means I would need to enlarge the operation extremely, to make it truly worthwhile. I do not have the space. Also, Autos don’t appear to be cloneable?

A few weeks ago I acquired a 1.5m x 2m x 2m growtent with lights and fans as well as a 1m x 1m x 1.8m. A friend had a tent, and kept 3 mothers in 24 hour light for me, so that we could continue to make clones all year long. Unfortunately it became too much of a burden to him, and I moved those mothers to my tent. I keep them on an 18/6 cycle, though.

What I would like to do is: keep mothers in the small tent (4 mothers) and clone from
them (let’s say every month/2weeks), so they will have to stay in the tent on 18/6. I will then incubate the clones in the large tent, and veg them for maybe two weeks, or even six weeks if it is a better option.

I would then like to move the vegged plants to the Greenhouse to flower. I am hoping to setup a cycle where I could then harvest several plants every month.

Month 1 - Make Clones A and Veg them after two weeks
Month 2 - Make Clones B and Veg them after two weeks
Month 3 - Move Veg A to Greenhouse, Make Clones C and Veg after two weeks
Month 4 - Move Veg B to Greenhouse, Make Clones E and Veg after two weeks
etc etc etc

In this way the mothers stay on a 18/6 cycle in the small tent, and the veg & incubating clones stay on an 18/6 cycle in the large tent. Flowering plants are on a shorter cycle in the Greenhouse due to the Sun.

I intend having the growtents inside the Greenhouse, against its SOUTH wall (in the N-hem it would have been the NORTH wall - the one which is away from all sunlight). The growtents can open up on three sides, thus I will leave their “unopenable” side against the South wall. I intend (as I presently do) to open the growtents every morning and close them every evening, thereby only having to use my lights for about 6 hours a day. The flowering plants will simply receive their normal sunlight, and when the growtents close in the evenings, they will not be confused because the growtent lights are sealed off when closed.

So, with all this info, my two main issues are:

  1. In the summer months, I would be able to save even more on electricity, because I can have the growtents open for longer hours, BUT, I assume that these longer sunlight hours will confuse any intended “flowering” plants as well, thus,
  2. I should actually leave the growtents open for ONLY 12 hours a day, and assume that I will have to find a way to BLACKOUT the Greenhouse if I wish to see the “flowering” plants triggered to their flowering by depriving them of light.

If these two points are correct, then it leads me to further questions:

  1. At which point exactly, at 25-26 degrees latitude, should one start being wary of “too long” light for the flowering plants? When I say “point” I refer to something like “first week of summer” or “at the equinox” or “second week of spring”.
  2. Does anyone know of sensible, relatively easy ways to blackout a small greenhouse on a daily basis?
  3. Just in relation to the plants themselves: if I plant light-cycle plants the first week of Spring, are they supposed to continue to veg until somewhere during the third month of summer, or are they supposed to switch to flowering shortly after the summer solstice? And, continuing on that point,
  4. Even though my plants (this year) switched to flowering around three weeks before the end of summer, they were not ready for harvest until the start of the third month of autumn (which is around 75 days - and ALL THREE the strains are indicated to have a 55 day flowering period). This does confuse me quite a bit. I can obviously understand that a plant will not take PRECISELY 55 days, BUT, surely a 20 day “lag” means I must be doing something wrong?
  5. Lastly, I’ve read on many websites that, apparently, in my latitudes, it is possible to do TWO crops in a year. How is this possible? If I plant in the beginning of Spring, then again beginning of Summer, will ALL the plants not reach harvest at middle Autumn? The second set of plants will simply have vegged for less? Or, do plants have another way of triggering earlier that I am unaware of? Surely the plants planted at the beginning of Spring will NOT flower before the summer is out, allowing another crop to be planted?

Here is more background (TLDR if you don’t need the background):
During the first year, due to negligence on the part of the expert who assisted me, we only planted the first seeds three weeks before summer (early November for me, June for Northern Hemisphere folks). The Autos went through their cycle and delivered (though humble, as mentioned), and the light-cycles continued their journey, being ready for harvest around the eighth week of autumn (end April for me, end October for N-hem - in fact, we started the harvest on 4/20). Great return, all fine.

During our winter, we tried some Autos again, that yielded better, but still not really worthwhile.

For my second year I ordered seeds myself, since the “specialist” who had assisted me in the first year, had now moved, but, of 40 seeds, only 6 actually popped. Many emails and arguments with the supplier yielded no results. I ordered new seeds from a different supplier, which arrived about six weeks into spring (middle of October for me, middle April if you’re N-Hem). I popped them and started the grow.

Something very strange happened (in my opinion), but this is part of where I need advice: about a day or two after the Summer solstice (21st Dec) one of my Triple Cheese plants (I had 5 TC and one Big-Bud-Northern-Lights BBNL) showed that it had started flowering. The others did not, and continued to veg for at least another month (they only started flowering about 2 to 3 weeks before the end of summer). I asked the one expert about it, and they said this is fine, since the hours in the day have turned. I did not have enough contact with this person to delve deeper and ask more about it, but it did seem strange, yet, nothing appeared to be wrong with the plant other than it was flowering “early”.

We had taken some clones and thus enlarged the grow to finally have about 40 or more plants growing. All the clones from that “early” flowering plant also flowered before the rest of the crop. All the clones from the other 4 TC and BBNL flowered more-or-less together.