She said substance, freshness and balance were paramount to a good bloom. The substance and freshness refers to the texture of the petals, while the balance is how it fits with its foliage.
Mrs McCullough said the exhibitors start preparing for the show weeks in advance, and a lot of skill went into having roses just right.
She said decisions such as when to prune and whether to cover the rose with an umbrella all played important parts.
This was the fourth time since the 1990s the national show has been held in Northland but Mrs McCullough said it could be the last, as the society is getting smaller and the members are getting older.
There are around 40 members, many of whom are in their 80s.