This crossword No. 26791 clues and answers were published on Wed 27 Jan 2016 and the puzzle can be visited by following The Guardian Cryptic Crossword No. 26791 link.
All Across Clues and Answers:
1-across – Ulcers a problem over a very long period : SECULAR
5-across – Bird loses right wing, American casualty of bigger gusts : PUFFIER
9-across – Platinum tongue-piercing : LATIN
10-across – Platonic relationship initially producing this hormone : PROLACTIN
11-across – Conductors preferred batons to include beech core : ELECTRODES
12-across – See 6 : FOOT
14-across – Return to cover sermon on a way the state changes : EVAPORATION
18-across – Settles deal — building to be decorated with mosaics : TESSELLATED
21-across – Horse managed to cross ring : ROAN
22-across – A farewell drink before riding iron vessel : STIRRUPCUP
25-across – Oxygen, say, emerges from parts of estate : HEIRLOOMS
26-across – Football team familiarly finishing season fifth in table : BORON
27-across – Lead and phosphorus sink : PRECEDE
28-across – Trees here tend to wither, if pollarded : NURSERY
All Down Clues and Answers:
1-down – Plate one exchanged for a set of cutlery : SILVER
2-down – Peasant farmer caught acting even more flamboyantly? : COTTER
3-down – Drew out pin around noon — after that, read intermittently : LENGTHENED
4-down – Imitation piece about inclined neon light : REPRO
5-down – Poet eating nothing with daughter, blooming exhausted : POOPEDOUT
6-down – Firm to pay for copper : FLAT
7-down – Grant entry to Mass, absorbed by hymn : INTROMIT
8-down – Nitrogen affected sound of handset : RINGTONE
13-down – No salt left! A terrible b-blunder : LANDLUBBER
15-down – Grant painter graphite, perhaps : ALLOTROPE
16-down – Features prominently on joint enterprise? : STARSHIP
17-down – At a function, carrying shabby clothes : ASTATINE
19-down – Start with carbon sequestration — it’s lacking : SCARCE
20-down – High-spirited double entendre has to stop — heavens! : SPUNKY
23-down – Synthetic compound controls essential movement of sulphur : RESIN
24-down – Oddly coloured lead : CLUE
This crossword has in total 30 where 14 are across and 16 are down.