"Kay" wrote in message
news
In article , Franz Heymann
notfranz.
writes


That is an urban legend. If there were any truth in it, all plants
planted in the open ground, which is an infinite sized pot for
practical purposes, should fail.

Up to a point, Open ground is much fuller with invertebrates, roots
of
other plants etc

True, but how would the absence of these components affect the
relative wellbeing of plants in "correctly sized" pots and those which
are "overpotted"?

I planted a very young Acer palmatum atropurpureum directly in a 45
cm
pot about eight years ago and have never repotted it. It thrives.

I think there's no problem with things that grow fairly quickly to
fill
the pot (even if its just the roots that fill it). It takes at least
a
year to get smelly compacted soil.

I have pots which have been in use with the same potting compost for
many years. I have never noticed any undue compaction or bad smells.
The pots which I use for growing half hardy plants like pelargoniums
usually just have the top quarter of the compost renewed each year.
My displays are no worse than those of my neighbour, who replaces all
his compost every year

Franz