Up to 6 plants, but no more than 3 in flowering, per adult up to 2 adults in most jurisdictions. That's 12 plants with 6 in flowering in a two adult household.

That's way more than enough. Here's how:

First, you keep a "mother plant". Currently about the best mother plant for the rootball would be a Skunk #1. Keep some vegetative branch or branches of that strain going.

Second, purchase feminized seeds. Start no more than four and keep in vegetative state. Flower a single clone from in a "screen of green" grow tent setting. At this point, you have the Skunk #1, 4 plants of the fem strain in veg, and one in flower.

Run each of the four in flowering until you find the best for keeping. Kill the other three. Take a cutting from the Skunk #1 to keep in veg and the new fem strain that you chose, then graft another clone from the fem plant to the skunk #1 mother plant. When that takes, you can safely kill both of the other clones and the original fem plant you kept. You now have one mother plant with two strains (Skunk #1 and the fem strain you chose).

Repeat as neceassary until you have all strains you want.

You now have a mother plant with multiple strains. Take cuttings you want to flower in three separate chambers.

Anything over an ounce in your possession when you complete the newest drying process, give away in 1 oz. increments. You can also convert to hashish for lower weights to meet that 1 oz. no legal ramifications limit Remember, between 1 and 2 oz in CO is civil offense that carries a $100 fine. You cannot legally sell anything you produce, but you can legally give away pot in no larger than 1 oz. increments with no penalty.

You can even form co-ops for trading of cuttings and dried cannabis. There's nothing at all illegal in doing that and you can insure nobody can be busted at all.

The best part is, the feds will completely ignore it because the potential federal felonies would be so small it simply is not worth their time and effort. Local authorities can do nothing because it is all on the up and up with CO law and everybody can hold a mother plant (1 single plant in the legal plant count) with over a dozen different strains to choose from to grow. You can have new strain of pot ready every two to three weeks and everything is legal!

The cannabis hating mayor of our town started making noises about limiting private cultivation. She was advised not to pursue the matter.
Prices are really falling in Colorado.