For increased growing rate and yield, try spraying your plants with an aspirin solution every three weeks.
1 - 325 mg. aspirin
Mash aspirin in 1 T Cider Vinegar
Add to a gallon of water
Hint for brighter plants:
Use a sodium-free seltzer water or club soda (let it get flat) and then use it to water your plants. Make sure it's at room temp. --- and then just sit back and watch it brighten up
Source: Internet