NY -- Standard&Poor's CreditWire 4/3/96 -- Standard&Poor's today has placed its double-`B'-plus rating of Scotts Co.'s senior subordinated debt on CreditWatch with negative implications. About $100 million of long-term debt is affected. The CreditWatch placement follows Scotts' announcement that 1996 earnings will be impaired as a result of earlier promotional programs relating to its consumer products business. Scotts' 1995 merger with Miracle Gro, financed with $195 million of convertible preferred stock, used a good portion of the company's financial capacity and flexibility, although the high profitability of Miracle Gro was expected to have an overall positive impact on cash flow. Debt protection measures were expected to show modest, short-term weakening. With the reduced earnings outlook for