In English, it's more natural to say "old and hard" than to say "hard and old". It's due to English having some rules about adjective ordering.
I think that's more relevant if they're hard because they're old, as then they are "old and hard", with "old and hard" being parsed as a single idea rather than two.
If the qualities are unrelated, this doesn't apply. For example, a classical Greek statue may be reasonably described as being both "hard" and "old".
Now, as apples don't tend to get harder when they get older (quite the contrary), this seems more of an incidental mentioning of the two attributes.
What are those rules?? I know English (not a native speaker) but I never heard about adjective ordering
Very soon a slow old train should come from my province.
The heading letters of each word mean:
Very — value
Soon — size
A slow — most other qualities
Old — age
Train — temperature
Should — shape
Come — color
From — origin
My — material
Province — purpose