World 1:This area is very easy, and is mainly just a tutorial to the game, Use whatever plants you have, this early in the game. But make sure you have peashooters and sunflowers.

World 2: Now this is when it gets a bit harder, the sun no longer falls from the sky, what I did was i used puff shrooms (the free mushrooms you get) and sun shrooms, then when I got that set up I would start setting up peashooters and repeaters. And at the end of the level, zombies spawn from the graves, so try to take them out early in the level (P.S. The graves give some good stuff, crystals, plants, and sun)

World 3: Ok you made it this far, now we are dealing with a completely different kind of strategy, what I did was I got lilipads, cattails (cattails are VERY strong, they can attack any lane, and they shoot two spikes at a time) I also had wall-nuts, cherry bombs (for emergencies) peashooters and repeaters. -- You want to make each lane equally strong. And make sure you buy the pool cleaners, they help a lot.

World 4: Ahh world 4, the hardest world in my opinion, basically its world 3 but you cant see half the screen, luckily you get a plantern in a level or two and you can see it then. I was stuck here for a while, but when I used cattails it was so much easier, just use the strategy from 3 and 4, i recommend at this point using sun flowers, and garden rakes (can be bought in Crazy Dave's shop for 200$" You REALLY want to use the torchwood, seeing as how they make your peas to DOUBLE damage. I personally have never really used the snow peas, but if your comfortable with them go ahead.

World 5: And last but not least, the roof level, make sure you buy the roof cleaners, you will need them. Here is what I did the whole time, first two columns are sun flowers, third column is cabbagepults, fourth column is corn pults, and fifth column is tall-nuts. When you get the melonpults I suggest replacing column two with them. As for cob pults, dont use them, they take too long, and they're not that good. Bungee zombies are best countered by umbrella leaves. Get one or two in each row, NO MORE, they protect the eight squares surrounding them, and their own. And my last tip for World 5, is gargantuans, here's the thing, if they didn't throw the imp off of their back, then cherry bombs would be all you need, however, I would advise using a cherry bomb, then using a jalapeno on the row, to kill the imp and the gargantuan.

Dr. Zomboss: This boss is very hard the first few times you fight him, so try doing this. Save all the ice shrooms and jalapenos you get, you need them to destroy his fire/ice balls. use all the other plants strategically to fight off the normal zombies. You WILL have to use ice shrooms and jalapenos occasionally, jsut save as many as you can.

How to earn a lot of money: Here is the best way without a doubt. You want to beat adventure and get your zen garden. Then play endless survival and adventure mode again to get plants. Water plants and mushrooms give you 10,000$ just to sell them and they give you 2 diamonds when they're grown to full, which pays for the food, and more. Normal plants like daytime plants and marigolds only give you 8,000$ to sell, but they give you two diamonds when grown to full. (Marigolds only give one diamond).