I don't see your point in moving the plants to another lot, but I did waste a lot of time in gardening, before. Automatic Sprinklers are awsome, but they *kiiiindaaaa* shorted my Simbot slave once every 4 days. I used the simbot just for the gardening, and for some reason it always wanted to be with the plants, even when the sprinklers turned on. It took too much work to care for that useless walking scrap, so I deleted him.
Now I just use the Harvest interaction when possible, and fertilize the plants when it's time. I don't use Weed and Tend Garden, because then the Sim wastes a lot of time with all the annoying weeds. I don't think they do anything, really, except for making the plants look ugly.
Also, half my garden is composed of Money Trees, so sometimes I just don't collect them at all.