by Connie Oswald Stofko You have to watch the weather and can’t rely on dates. If you wanted to plant tender vegetables on Mother’s Day or Memorial Day this year, you’re probably feeling disappointed right now. Many parts of Western New York had frost warnings last night. Even if you didn’t get frost, it was too cool overnight for tender plants, such as tomatoes. “Not just tomatoes, said Patti Jablonski-Dopkin, general manager at Urban Roots Cooperative Garden Market. “I’d be careful of…