We did a whistle-stop tour last year - about this time, my other half's first visit to Zuffolk. As the year progresses things get dusty and by August, harvest is all but done and to me the landscape is less attractive.
It was timed perfectly, the weather was very warm rather than hot, hazy blue skies, everything was green and fresh. Early start from Horseheath (Old Red Lion Inn - highly recommended), Haverhill, Clare, Long Melford, Nayland (the Crown's smokehouse was more than well worth a visit), Stoke-by-Nayland, via the stunning ridge road to Stratford St Mary, Dedham, Lawford, Cattawade, Holbrook (through the school), along the road that follows the south bank of the Orwell, over the Orwell bridge, Snape, Southwold.
Even my other half, a west-country girl, wedded to Devon in particular, fell in love with Zuffolk and the Stour valley in particular (the Stour is the boundary Suffolk-Essex, so not strictly speaking entirely Suffolk).