Dolomitic Lime Dated 2009 – Is It Still Useful?

Q: For tomatoes. I found a box of agricultural dolomitic lime in our dry basement dated 2009. It is still powdery, no clumps. Is it still useful? 

A: Lime deteriorates slowly, even when it gets wet. Since your lime is dry and powdery, it is just as effective for soil application today as it was nine years ago.