If you are waiting for plants to grow, you are doing it wrong. Specially in regrowth, because there are not weeds.
* To improve stats of seeds, prepare a line of 15 more or less crops, plant 1 seed and go do something else
* To crossbread, don't do just 1 cross. Do like 6 at the same time. Crossbread can fail, but if you have 6 chances, is more probable to get the cross.
* While waiting, specially in early game, expand your base. Place a 2 or 3 high wall around everything.
Yeah I know, This isn't my first run through regrowth just had to restart due to a derp:
Due to a huge mistake on my part it looks like i'll be going into 0.8.6 with a new world
Decided to move the location of my base by shoving everything into ME Drives then into chests within chest into bags within a chest in my inventory.
Turns out all that data in ones inventory is too much for the client to handle and crashes on entering the world.
On the bright side i was getting bored with having everything and wanted a fresh start, now's my chance.