I rooted some gardenias a year or two ago and they never did much. Just sat in their little pots dying back and looking anemic. I threw out all but one. I was planning to throw it out too, but then I got lazy. I didn't want to take the time to water it, so I just stuck it under the runoff zone for a plant that was up on a stand.

Here's where it gets interesting. The plant on the stand was potted up in pure homemade compost. Again, I was too lazy to open the bag of potting soil etc. It was just a lot easier to scoop a shovelfull of compost out and stick the plants in.

The water dripping out of that plant on the stand was basically compost tea. After one or two vicarious waterings, the little gardenia greened up and started growing- fast! I'm going to have to put it in the ground soon, it's so healthy. If ever I doubted that all those banana peels and coffee grinds were good for the garden, I'm sure now!