Carol Klein's garden is Glebe Cottage in Warkleigh, Devon and according
to this slightly out of date reference, it's open on a couple of
Sundays in March:

Find an open garden (maybe!) at http://www.ngs.org.uk/search1.htm

Glebe Cottage is open in 2004 on

22 February 2004
21 March 2004
11 April 2004
25 April 2004
09 May 2004
06 June 2004 ---- next open day
27 June 2004
11 July 2004
25 July 2004
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Thanks for the replies, and spelling correction ;-)

Unfortunately, we are not around that area on 6th June. Perhaps another
time...............

Best wishes for a blooming summer.
Marina.