Ole was due to begin shortly before turning six but, said his mother, "he wasn't at all able to look after himself, he got easily frustrated if he couldn't do something.... He still needed a bit of time."
He stayed in kindergarten a year longer which was the right decision, Wesenberg said. "It turned out as we expected. Now he feels fine at school," she told AFP.
Six percent of children who started school in Germany in 2011-12 were those who had postponed entry, nearly two-thirds of them boys, according to data from the federal statistics office, Destatis. But the figure is far higher in some regions.
Some 3.8 percent, on the other hand, were early-starters.
Fifteen years ago German authorities sought to bring forward the age that children begin school to the calendar year in which they turn six, to be more in tune with other European countries and due to a pressing labour force shortage.
A year was also sliced off high school in many places.
But the proposed nationwide change didn't factor in objections from those parents who believe it is still too early for their youngsters to face the stresses and strains of formal school life.
"You very often hear talk of stress at school, pressure and suddenly parents ask themselves if they can inflict that on their child," said Helga Ulbricht, who heads an advice centre on school matters in the southern city of Munich.
In Bavaria state, where the centre is located, nearly 12 percent of school entries are delayed.
Faced with this kind of parental resistance, the Bavarian authorities, like most other regions -- education is run by the German states -- were forced to abandon the initiative for school entry in the year of a child's sixth birthday.
It is now the norm only in a handful of regions, including Berlin.
Among specialists, opinion on the issue is divided.
Peter Struck, a professor emeritus in education from Hamburg University, argued that "the earlier children begin, the better they learn".
He conceded, however, that starting school later can be beneficial for children who still do not have a good command of language or who have developmental delays.
For her part, Beate Koegler, a Bavaria-based educationalist specialised in language problems, said parents' fears "aren't exaggerated".
"School is actually very demanding," she said.
Koegler said she backed deferring school if the extra time is used "to carefully see in which area the child needs targeted support to be better equipped for starting school the following year".
But for some German parents, it may be a problem of image.
Many have "a critical idea of school that they see as the end of childhood", Katharina Kluczniok, a pedagogic researcher at Bamberg University, said.
"You may also ask yourself whether the parents don't want to give themselves an extra year of respite" before homework and strict timetables set in, she added.
Ulbricht highlighted how big a change starting school can be -- also for the parents. "It's a big step for the parents to recognise 'that's it, they're ready'," she said.
And Germany's low birth rate may add to parental pressure, she said, adding it could be even harder for parents to let go when the child is an only one, or has just one other sibling.
German women have on average 1.3 children, among the lowest rates in the industrialised world.
But, warn some experts, keeping children away from school for as long as possible is not necessarily doing them any favours.
Late-starters "don't reap big advantages for their school careers or in terms of capabilities", Kluczniok said. "On the contrary they often finish with fewer qualifications" than other youngsters, she added.
Manja Plehn, who teaches at the Elisabethenstift educational academy in western Darmstadt, shared the concerns.
"Parents assume that children are going to gain in terms of their ability to concentrate, their aptitude to learn etcetera, simply from the fact of them being given more time.
"But this approach is clearly refuted" by the research, she said.
Many kindergartens where children end up staying on longer do not have programmes specifically designed to ready them for school.
However some schools do run preparatory classes to help children adjust from kindergarten to the new challenges, such as learning to read.
Kathrin Kuehne-Giese sent her son Lovis to one such school in western Frankfurt in the year he turned six.
"What I'd like is for there to be classes like that across all of Germany," she enthused.
"That would be the way to ensure that all children are ready."