I wouldn't recommend using mutation unless you have also upgrade your soil. You may end up with a plant that won't survive at all.

There are other common seeds that will help you get to a Fourpetal Maple through the store, including getting that plant itself.

Do you have other common seeds saved?

If you don't want for the next day's seeds supply, you may want to consider starting a new game in another slot and being more careful about saving your common seeds.