Laymon Jackson was born in Atlanta on April 4, 1932 and attended David T. Howard High School. He enlisted in the Army, played music during his service, and moved to New York in 1959. Those biographical details come from a single compiled source (the Discogs artist profile, which cites two 1993 Atlanta obituary clippings) rather than from a published biography, and no book-length or encyclopedia treatment of his life exists.

His recorded career in New York was short and concentrated: every studio and location date that carries his name falls between March 1959 and May 1961. The first was Nat Adderley's Much Brass, cut in New York on March 23 and 27, 1959 for Riverside, where Jackson is credited on tuba as well as bass in a sextet with Slide Hampton, Wynton Kelly, Sam Jones, and Albert Heath. That doubling is unusual for a working bassist of the period and is the one credit in his catalog that puts him on a brass instrument.

Blue Note used him twice for Lou Donaldson. He is the bassist on the October 31, 1959 session at Van Gelder Studio that supplied most of The Time Is Right (BLP 4025), a date with Blue Mitchell, Horace Parlan, Dave Bailey, and Ray Barretto on congas; the LP jacket and the Blue Note session sheets garble his name as "Jack Laymon." He returned on February 28, 1960 for four of the eight titles on Sunny Side Up (BLP 4036), with Bill Hardman, Parlan, and Al Harewood. On both albums Sam Jones covers the remaining session, so the two bassists split each record.

The eighteen months that followed put Jackson inside one of the better working quintets of the early 1960s. He held the bass chair in the Donald Byrd and Pepper Adams group, and Blue Note recorded four sets of the band at the Half Note in Manhattan on November 11, 1960 with Duke Pearson on piano and Lex Humphries on drums. The tapes were split into At the Half Note Cafe Vol. 1 (BLP 4060, 1961) and Vol. 2 (BLP 4061, 1963). Early in 1961 the same front line went into a New York studio for Teddy Charles's Warwick label with Herbie Hancock on piano and Jimmy Cobb on drums; that session became Out of This World (Warwick W 2041), an album later recycled under at least four other titles including Takin' Care of Business, Jammin' with Herbie Hancock, and Birdhouse. On May 2, 1961 Jackson made his last documented New York record, Byrd's The Cat Walk (BLP 4075), with Pearson back on piano and Philly Joe Jones on drums.

After that the New York trail stops. Jackson returned to Atlanta and spent the rest of his working life there as the bassist in pianist Paul Mitchell's trio, with Allen Murphy on drums. Verve recorded the group live at the Atlanta Playboy Club on August 24, 1966 and issued it as Live at the Atlanta Playboy Club (V/V6-8713, 1967), produced by Tom Wilson; the sleeve spells him "Layman Jackson." The trio then settled into the residency it is remembered for, playing six nights a week at Dante Stephensen's fondue restaurant Dante's Down the Hatch, and cut Another Way to Feel (1973) for the club's own Dante's Down the Hatch label. Jackson also backed Teddy Wilson on an August 17, 1980 club date in Atlanta that was later released as Moonglow: Live at EJ's, and by the mid-1980s was leading his own trio with Allen Murphy and George Dogias. He passed away in Atlanta on October 7, 1993, and his widow attended the closing night of Dante's Down the Hatch.

Jackson's playing is best judged from the Half Note tapes, where the recording is close enough to hear him clearly across four sets: a firm, unhurried walk with a big woody sound, holding tempo behind Pepper Adams's baritone without crowding it, and taking almost no solo space. He was hired for that reliability rather than for display, which is why he turns up on hard-bop dates for two labels in three years and then disappears from the New York studios entirely. His tuba work on Much Brass is the only surviving evidence of a second instrument. Nobody has written a critical assessment of him, and the review literature on the albums he played on (AllMusic, the Penguin Guide) discusses the horns and the pianists without naming the bassist. One online forum claim that he was the second most recorded bassist after Ron Carter is plainly wrong: his verified catalog runs to roughly ten sessions.