Do I Need to Stake My SEED in Sprout?

You do not need to stake your SEED!

But if you meant if you need to stake in Sprout in order to earn SEED, that is not necessary either. Stake with Sesameseed from any wallet (on Ontology, make sure you are using our custom smart contract).

You can also hold your SEED on any wallet on any blockchain on which Sesameseed is giving out rewards.

Of course, it is highly recommended you have an account with Sprout. It is the only wallet in the world where you can swap SEED between chains and have access to the full redeem value (since you need addresses on multiple blockchains).