by Connie Oswald Stofko Whether you’ve signed up to exhibit your garden on one of the 17 garden walks that are part of the National Garden Festival in Buffalo, or whether you’re expecting company, you want it to look its best. Sally Cunningham, project coordinator for the the National Garden Festival in Buffalo (now Gardens Buffalo Niagara), shares some tips. She is a horticulturist, author and garden consultant. You can catch her weekly on WIVB-TV (Channel 4) on Sunday Mornings, 8…