Perhaps not for ever, but treating with flowers of sulphur
or adding large quantities of peat will produce the right growing conditions and is preferred to filling planting holes with an ericaceous mixture.
EXAMINE stored dahlia tubers and cut off parts that are showing signs of rotting and dust with flowers of sulphur
, and if they are shrivelling plunge them in tepid water for the night, dry and repack them in trays of peat.
If there are any signs of rot them cut off the affected parts and dust with flowers of sulphur
Rubbing off damp soil and cutting off leaves will help, and you could then put them in an airing cupboard for a few days to dry out, before dusting them with flowers of sulphur
For a sandy loam, 125 grams per square metre (4 oz per sq yard) of flowers of sulphur
is sufficient, but double this quantity for heavy loams.