The message
from Janet Tweedy contains these words:

Does that mean tidy and immaculate 'well cared for' or packed with pots
and plants and compost and stuff because you spend too long in it?
What I mean is, does a garden with rare plants or interesting ones sell
as well as one that has very easy plants and shrubs. Does rarity
frighten people?

The kind of person who recognises rare plants is highly likely to be a
keen gardener, and will therefore view them with delight. Those who
don't recognise rare plants won't be intimidated by their rarity, will
they? :-) The trick is to pick up FAST as many clues as you can from
each viewer about what their particular interests are, and play to them.
If they exclaim "wow, what a big parrotia over there", you say "Ah, if
you like my parrotia,wait till you see the stewartia". If the viewers
are as weird as hell and have out-of-control twins aged 4, mention the
total privacy and secure boundaries instead.

I know when we had our house valued the agents did say that some people
would be put off by 200 foot of garden even though we had 4 bedrooms and
presumably could accommodate a family.

Sounds like a bum agent to me. One worth their salt would say "I shall
market this house to buyers who actively seek a big garden". There are
zillions in that category, for lots of reasons.. keen
gardeners/naturists/naturalists/hen-keepers/parents of active
children/owners of large dogs/ aviaries/people who like peace and
privacy/want space for a pool/hobby-room etc.

When we put our last place on the market (small 3 bed house, just
under 4 acres) an excellent agent, doing just that, produced a
record-breaking, utterly exhausting 170 viewers in a fortnight and sold
it in three weeks. (The Scottish system moves fast). What astonished me
was that all the 13 serious bidders were moving either from a gardenless
town flat, or a much larger, grander suburban house with a very tiny
garden.

Janet