Will I be able to get all the plants without spending money?

When picking plants for a level, I notice there are plants like the Snowpea that I could use, if I spend a little real world money. Will I eventually be able to use all of the plants in the game by progressing naturally, or will I have to spend cash to use them?

If there are plants which must be bought using real money, which ones are they?

Solution 1:

No you cannot.

These plants must be purchased:

• Snow Pea
• Torchwood
• Jalapeno
• Power Lily
• Squash
• Imitator

I've completed the entire game and have not unlocked these.

On top of that, there are also purchase only bonus powers. You will be able to find one of each upgrade through the game, but the second one must be purchased.

• Shovel Bonus
• Plant Food Bonus
• Sun Bonus
• Bonus Seed Slot