Which are the Halloween plants and are they available for Gems in shop ??

@Abhay_ZombieWolF You can unlock SP by playing Penny's Pursuit. You can earn 60 seeds every day...so you can get 6*60 = 360 seeds during the event. In addition you'll get some additional seeds by completing some of the levels.

Shadowpea seeds will also be in the store but the offer will work like the Murkadamia Nut offer. It'll start with 10 gems and increases by 3 gems each time you buy a Pinata.