Board Thread:Plants vs. Zombies 2: It's About Time/@comment-25475672-20140927115547/@comment-24860884-20140930005059

I think either Sun Shroom or Twin Sunf.

Sunshroom: It's cheaper and less cost than TS. So you can spend it on Lily Pads. Has to wait a while to make sun about  the sun made by TS. Can be planted w/o waiting for sun(in the beginning)

TS: Saves More space  . 100 sun production at a constant unchaning rate, but you have to wait for a sun to fall down (assuming you have at LEAST one of the boosts.  Space is Important when limited land