I've seen this on my plants multiple times. You can either take advise from someone that's seen it before, or from someone that's got a PhD in internet browsing. Here's my remedy for just about everything. You can use it all the way through flower. Very safe. For any plants. I use it on my...
I like to place rotten material in the bottom of the hole. As it decomposes, it amends the soil for you. So, by time those roots reach down, they're receiving all those goodies. Cheap and very efficient.
They won't grow. The sap becomes thick when cold. They will tolerate the cold(depending on the strain and how healthy) and continue to grow when the temp rises again and warms the sap. I live in Michigan and frost is by far the number one issue(aphids, gnats and mites.. and piece of shit...
Growing outdoors has so many problems that you're going to face. Humidity and temp are going to have a huge impact on bud development. If both aren't dialed in, your going to have light airy buds, which really isn't bad(I'd rather by an ounce of light buds, than an ounce of those hard pgr...