Fruits and leafy vegetables may be used for blending if they have been thoroughly washed and blended well without checking.
Fresh strawberries can be washed and agitated with soap, no checking required and then blended.
Frozen non-organic strawberries and blueberries without additives may be used without Hashgacha for blending. Some are strict to rinse them before using.
Frozen blackberries and raspberries and organic strawberries (as is commonly infested) - a) some allow to blend as is, b) some say it must be rinsed well before finely pureeing.