Talk:Fungus Humongous/@comment-11300816-20140626102434

First stage you can do this is Dark Ages Level 3 because you need 2 plant food. Use back row for Sun-Shrooms. Then you'll need 4 rows of puff-shrooms. Start off building you're back row while you get rid of the gravestones. You need to keep planting puff-shrooms as soon as they are ready.

Once you have enough sun start building your defenses by placing Tal-nuts on row 6, ideally you want Tal-nuts on row 7 as well but use whatever nuts you have available.

Once you have your defenses and the front 2 rows behind the tal-nuts filled with puff-shrooms (they'll be expiring soon) use a plant food, this renews their timer.

From here on out fill the back rows ASAP and re-plant your nuts as needed. once you have 4 rows filled, use a plant food ASAP, and hopefully you'll get the achievement.

I had 3 puff-shrooms disappear after I activated the plant food but still got the achievement. Timing is very tight, you need to be very quick laying down the puff-shrooms.

Note: I did this without any IAP plants.