Scotts Seaboard Corp., which operates the 17 Scott's Home and Garden Centers in the Baltimore-Washington area, said sales increased 37 percent to $35.3 million for the year ended Jan. 29, but the company lost $437,000.

Scotts had a loss of $590,000 the year before, on sales of $25.8 million. The company, based in Linthicum, Md., also owns Seaboard Plywood and Lumber Corp.

Among the things Scotts cited as causes for its losses were a "difficult economic environment . . . adverse weather conditions . . . increased interest expense" associated with its expansion last year.

For the latest quarter, Scotts had a loss of $105,000, down sharply from the loss of $850,000 in the comparable quarter last year. Sales increased to $7.8 million from $6.6 million. E. I. L. Instruments Inc. of Sparks, Md., had a loss of $70,000 in its first quarter ended Jan. 31, compared with earnings of $167,000 (12 cents a share) last year. Revenues were up slightly to $5.8 million from $5.6 million.

E.I.L. distributes, customizes and services instruments for test, measurement and control, and builds electrical testing and measuring equipment.

Balance Computer Corp. of Hunt Valley, Md., posted profits of $65,131 (2 cents) for its third quarter ended Jan. 31, compared with a loss of $354,180 the year before, while revenues grew to $1.1 million from $342,121.

For the nine months of the fiscal year, the company lost $303,735 on revenues of $2.7 million, compared with a loss of $493,423 on revenues of $1.4 million last year.