Hi Caroline
I can't find him in 1851

Maybe someone has better eyes for him than me!!
I see he married Jun Qtr 1852 in Dorchester, Dorset to Mary ROPER - and by time daughter born around 1858/59 they were in Plumstead Kent and still there on 1861, 1871, 1881 Census...... remarried 1883 to Ann; still in Kent 1891 and 1901.
A Blacksmith by trade in 1861, 1871, 1881, retired Blacksmith 1891, 1901. Age is consistent in Censii, and so is birthplace (though with various spellings)
I notice in 1881 his ful Occ. is "Blacksmith Royal Arsenal"
And also, Plumstead is in the Woolwich RD of Kent. Woolwich was where there is/was an Army base/depot I think?
Also, in 1891 he is indexed as living in "Town West India Dock, London" - not sure if this is some kind of index 'linking' error - the actual image says he is is in Plumstead and on same street (Cresent St) as in earlier Census.
Does this sound like he may have been an Army Blacksmith and may have done his apprenticeship that way - may explain being unable to locate him in 1851???
Here are his parents in 1851, though!
1851 - Charminster Dorset RD : Dorchester Sub-RD : Maiden Newton ED: 1
REF : Class: HO107; Piece: 1858; Folio: 415; Page: 34
Head: Alfred OLD 55 Dairyman, b Glanville Wooten Dorset
Wife: Martha OLD 56, b Mapperton Dorset
Dau: Angia OLD 26, unm b Glanville Wootton Dorset
Dau: Mary OLD 15, b Buckland Newton Dorset
Dau: Margaret OLD 14 b Buckland Newton Dorset
Son: ALfred OLD 12, b Buckland Newton Dorset
Dau: Maria OLD 9 b Buckland Newton Dorset
Visitor: Richard OLD, 21, unm, Carpenter, b Glanville Wooten Dorset
Cheers
AMBLY