Cucumber launched with under a million viewers on Thursday evening, overnight figures reveal.
Russell T Davies's new Channel 4 series brought in an average 973,000 viewers (4.3%) at 9pm, with an added 259,000 (1.7%) on +1.
Companion show Banana opened to 341,000 (2.0%) viewers on E4 at 10pm.
Earlier on Channel 4, Location, Location, Location appealed to 1.49m (6.4%) at 8pm (334k/1.5% on +1), while Josie Cunningham: The Most Hated Woman in Britain? fascinated 1.08m (7.0%) at 10pm (251k/3.0%).
BBC One's Death in Paradise topped the night with 6.50m (29.0%) at 9pm. Room 101 amused 3.91m (17.5%) in a new Thursday slot at 8pm, while Question Time was seen by 2.36m (21.8%) at 10.35pm.
On BBC Two, Winterwatch gathered 2.62m (11.3%) at 8pm, followed by Winterwatch Unsprung with 1.47m (6.5%) at 9pm. Surviving the Holocaust was seen by 1.24m (6.3%) at 9.30pm.
ITV's pepper-spray edition of The Kyle Files attracted 2.69m (12.8%) at 7.30pm (128k/0.5%). Birds of a Feather entertained 2.95m (12.3%) at 8.30pm (209k/0.9%), while Bring Back Borstal brought in 1.54m (6.9%) at 9pm (183k/1.2%).
On Channel 5, Benefits: Can't Work, Won't Work intrigued 1.22m (5.3%) at 8pm (153k/0.7%). Celebrity Big Brother continued with 2.32m (10.3%) at 9pm (327k/2.1%), followed by Botched Up Bodies with 742k (4.7%) at 10pm.
E4's Big Bang Theory tickled 1.36m (5.7%) at 8.30pm (360k/1.6%), followed by Brooklyn Nine-Nine with 595k (2.6%) at 9pm (105k/0.6%).
Ross Kemp's Extreme World returned with 383k (1.7%) at 9pm on Sky1.
