Usually when I do a seed project grows, I let those plants bloom past their usual finish dates from their mother and father strains I used.... say mom was a 58 day strain.... and dad was a hybrid say 63 day strain bloom finish, I would then go at least 68 to 70 days bloom altogether, To make sure I have majority mature seeds say 80% mature dark brown 20% white immature seed cause you will never achieve full 100% all mature seeds, plus taking into consideration the turn over week if working indoors from 18/6 to 12/12 light cycle. there is usually a week sometimes two of a turn over from growth to bloom stage for the plant. Then from then on I try to keep count of the bloom days and make sure my girls finish late and collect the mature seeds and pull and collect the male pollen sacs and save those separately for future use. Therefore nothing is wasted female or male since I put the time and money in to growing them both. And yes lol.... tent wise fun ...fun... cleaning that each seed grow, but so worth the reward of the bounty of seeds and pollen I'm given for future grows.... As for outside that's up to my girl mother nature I let those ride till its too cold to be outside for a pregnant pot plant in mid to late October. Then its chop time harvest dry, cure, collect seeds ... Then I take the remaining plant matter decarb it and make tinctures, edibles or hash mixed with dry trimmings.... lol no waste!
If limited for space right now and you still have a itch to breed seed or grow, You should see if some of your friends will help you out and do a collaborative seed grow one house backyard males or in the house, Then far enough away a second house yard or in house of females and then a third person house for bloom yard or in house, ...So with mother nature and time or lights in house, You can have a seed project with what you have and become closer friends with your grow buddy's and also in the end having a lot of seeds to play with in future grows plus pollen if someone wants to harvest that too! lol