Behind me are the monster cosmos that I grew from seed this year... and in front of me is a monster basil. What's my gardening secret? Brag about the one good gardening year I've ever had and don't tell you about the previous years :)
Okay, I put 2 cubic feet of compost in this little garden in the spring. Plus, if you look closely at the lower-left corner of the photo, you'll see the timer for my watering system. The timer is much better at watering than I am. And to make it even better, this particular spot in my yard gets plenty of extra water that drips off the roof and plenty of afternoon shade. I tripled the size of this flower bed when I noticed that the weeds and grass do so well in this spot.