If he succeeds, he will become the first player to successfully defend the title since Harry Ashby beat Carl Mason at Formby in 1973.
Foster, 20, was in sparkling form in both his quarter-final and semi- final. He was five under par when beating Northumberland's Iain Ferrie at the 15th, and four under when seeing off Robert McGuirk from Princes at the 14th.
Foster was in total command against McGuirk, after recovering from early errors at the second and third as he three-putted, then almost went out of bounds. He lost only one hole in his morning match and one in the afternoon.
His final opponent, the 23-year-old Jarman, has competed three times before in this championship, his previous best performance came when he the second round.
Jarman won his quarter-final three and one against the Yorkshireman Jamie Miller, but in his semi-final, against the England Boys international Shaun Webster from Sussex, he was never ahead until holing a putt for a winning par four on the 18th green.
In Scotland, international team-mates Hugh McKibbin and Simon Mackenzie will meet in the 36-hole final of the J&B Amateur Championship at Southerness today. The 21-year-old McKibbin, the defending champion, is aiming to become only the fourth player in the event's 73-year history to win consecutive titles. He has been burning up the scorched, unpredictable fairways, recording a two-under-par total for his seven matches.
Although Mackenzie's figures for the week have not been nearly as impressive, the 25-year-old can claim to have never been behind in any of his seven outings.
McKibbin booked his place in the final with a 5 and 4 victory over Allan Turnbull, after having earlier in the day ousted Gavin Paterson on the final green of an intriguing quarter-final tie.Reuse content