12 Lightly touching on love for farming method (4,7)
ZERO GRAZING - ZERO = 0 = love + GRAZING = lightly touching

14 Means to improve reputation with posh girl (3)
PRU - P(ublic) R(elations) + U (posh) = PRU(dence), as a woman's name

15 Artistic movement of green and white horse? (3,4)
NEW WAVE - NEW = green; waves are sometimes called 'white horses'

17 A division of history of equestrian art? (6)
RIDING - dd - a 'riding' used to be part of a county, as in the West Riding of Yorkshire a measure of the distance you could ride around in a day

19 Plays in ways not conforming to expectation? (6)
STRUTS - I guess this has RUT (conforming to expectation) inside STS = streets/way, so there's a play on 'not in a rut'

21 Local brewing house opens to provide it? (7)
ALCOHOL - (local h o)*

23 Return of legendary winger's brother (3)
COR - This is 'Brother!' as in the exclamation, and also ROC rev.

24 Fresher you mentored in biblical work (11)
DEUTERONOMY - (you mentored)*

26 Gets gunboat back defying odds in exploit (5)
ABUSE - alternate letters of 'gets gunboat' rev.

27 Old province of Asia, until dissolved (9)
LUSITANIA - (asia until)*

29 Turnover from enterprise initially millions a year -  then nothing (8)
EMPANADA - Spanish pancake thingy, so a 'turnover' = E(nterprise) + M + PA (per annum) + NADA - appropriately, in Spanish

30 Put out by kiss that’s tender but worth very little (6)
KOPECK - KO (knockout + PECK - this was Russian money (legal tender); a hundredth of a rouble, I think

1 Go after second rate reading matter, attacking furiously (8)
BLITZING - ZING (go) after B (second rate) LIT(erature) - from the German Blitzkrieg = lightning war

2 Note Cockney’s kindness being spoken of (5)
FIVER - intended to be a homophone for a London Eastender saying 'favour'

3 Bearing the strain (3)
AIR - dd

5 Is owner of bank considered? Not so (7)
HASTIER - HAS = is owner + TIER (bank - in a grandstand - if an action is hastier, it's not considered; FOI

6 Trumpet-blowing of dance music dwarf covered in life story (11)
BRAGGADOCIO - loose (metaphorical) definition - RAGGA (dance music ) + DOC (one of the seven dwarves) inside BIO (life story ) - I hadn't heard of RAGGA; apparently it has something to do with reggae

7 Run in with box for tool (4,5)
NAIL PUNCH - NAIL here means 'arrest'

8 Those in favour tipped 17 for promotion, maybe (4,2)
STEP UP - PETS rev. + UP, referring to 17a - 'riding' = UP

9 What a welcome for Mary after start of birthday function (6)
BEHAVE - B(irthday) + EH (what?) + AVE (Maria

13 Really fancy package, round, wrapped by West lndian (2,1,6,2)
GO A BUNDLE ON - expression from betting on horse-races; BUNDLE + O (round) inside GOAN - someone one from Goa, an island west of the Indian subcontinent (so not WI)

16 No ducking the consequences of its successful negotiation? (5,4)
WATER JUMP - cryptic definition - if you negotiate the water jump successfully (in the steeplechase) you may avoid getting wet

18 After filming, maybe, run to take on champion (8)
PLAYBACK - PLAY (take on in a game) + BACK = support = champion

20 Declined to hug as filthy (7)
SQUALID - QUA (as) inside SLID (declined)

21 Answer kid’s composed (2,4)
AT EASE - A(nswer) + TEASE

22 Mountaineering aid seen in distance, above fell (3,3)
ICE AXE - ICE = distance, as in look at someone with an 'icy stare' + AXE = fell

25 Large feline in spring, heading off (5)
OUNCE - another word for a snow leopard - (p)OUNCE

28 Tango without what it takes? (3)
TWO - T(ango) + W(ith)O(ut) - 'it takes two to tango'