Here in Central east Missouri, about Oct 1
I put my 3 Gal cloth grow bags inside of large plastic plant pots (usually I can get these from my local nursery for free or just a few dollars apiece) & Put several inches of mulch on the inside bottom, then I fill the insides of the Lg planters with Mulch… and put another 2 inches of my soil mixture on top of the actual cloth pot…
Then I have gotten myself very large moving boxes which I take cut up and build mini greenhouses with and put around my plants,(two pieces of cardboard thick and duct tape works wonders) I use Velcro strips glued on the box to Close them up once they’re on top of the plants and around the bottom plastic potters(because during the day I take them down and lay them flat or cover them with plastic if we’re supposed to get rain) …use an old sheet, black weed mat or burlap bag over the tops of the boxes when set up to keep frost out… allowing fresh air but keeping the dreadful frost off my plants preventing rot …
This is at night time, in the morning as soon as I can I remove everything except the plastic potters, the root ball is the most important part of the plant to stay “warm”,,,i’ve also used 3 1/2 inches of insulation around the inside of the plastic pot as well with the cloth grow bag in the center.
I will poke a few holes in the cardboard as well as in the plastic potter I’ll punch about 40 holes using a quarter inch drill, Allowing oxygen to get to the plants roots/plant…
I’m in MO & this works great
We start to see our first frost usually during the third or fourth week of October…Sometimes my plants will go till the end of first week of November… using this method.
Never had a problem with bud rot or anything else…
A friend of mine that grows in the MO hills in soil uses large poles he’s driven into the ground & placed a tarp over the polls over the plants at night he also insulates the ground with straw around the base of the plants. He grows large photos up to 8 feet tall mainly because he bends them over when they reach a certain height. He lets his plants go until the first or second week of November. But he’s retired and doesn’t plan any trips in October early November so if it’s going to rain or frost he’s always available to put his tarp over the plants (He does have air holes cut on the lower part of the top for air)!
Info from different articles:
—Water using 70f plus
H2O… & always Cover plants with waterproof material during fall when dew & rain come at night
or day (shake plants dry if it rains during day and cool at night).
Plants will tolerate the occasional nighttime low temperatures of around 10ºC/50f, but not for extended periods. If temperatures get too cold, around and below 10ºC/50f the plant will struggle to absorb nutrients and may be unable to absorb sufficient Phosphorus. This is known as nutrient lock-out, the necessary nutrients may be present but due to cold (or incorrect pH) the nutrients can’t be effectively absorbed. Make sure feed water is warmer than usual if possible, have 5 gallon buckets on hand…74-78f.
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Once outdoor temperatures dip much below 15ºC/59f growth rates tend to slow dramatically.
Cold roots simply can’t grow rapidly. If the root zone is left too cold for too long plant health will soon start to suffer and growth rates will slow. Indoor growers with plant containers positioned on a cold concrete floor will see the same issue.
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The cold, being a considerable stress upon the plant, triggers changes in the plant's metabolism which, when they occur in the final stages of flowering, can lead to an increased resin production. If we gradually lower temperatures to around 61f the last two weeks of bloom, once the buds are fully grown and only need to mature, it's possible to achieve a much greater and higher quality resin coverage in exchange for only a very slight sacrifice in production weight. Applying UVB Supplemental lighting if possible will also enhance cannabinoid production mainly THC by ~20%
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Fall:
cooler temperatures inhibit chlorophyll production. For cannabis, depending on the lineage of the strain, certain colors can appear when you drop the temperature and the light cycle shortens, simulating a change in season.
The ideal range to grow cannabis is a pH of 5.5-6.5, however, during flowering, you can lean one way or another to enhance or minimize certain anthocyanins to bring out certain colors. Additionally, different strains of cannabis come with different cannabinoid ratios, flavor profiles and anthocyanins.
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Tip: If frost is expected, water your plants in the evening. This protects the roots from freezing.
(place them in a spot that gets direct
sunlight in the morning. The reason for this is that it is better when plants can slowly defrost after a night of chill. This way, your plants may even be able to survive nights that drop below their healthy threshold for development. Growing spots near a lake or river can also be very good. They are naturally a few degrees warmer, so there is less risk for frost at night.)
