Despite the two errors, the fundraising was a great success, raising a "fantastic" £75,000, said RHS head of press Lynn Beddoe - enough to buy 25,000 trees - and even received donations from those who complained but were prepared to overlook the leaflet's errors.
RHS Hyde Hall in Essex issued 40,000 leaflets asking for donations to plant 35,000 trees costing £100,000 at the site over the next seven years.
Beddoe said: "We are very obviously aware of the mistakes. They are not something the RHS takes lightly because we pride ourselves on knowing our plants. The head of development was very apologetic. This was down to a printing error with a stock shot not thoroughly proofed. We only received a handful of letters pointing out the errors. We apologised and explained."
A previous appeal replanted an "arable desert" and was one of the RHS's most successful ever. The appeal has helped plant 50,000 ash, elder, silver birch and oak trees on the Westerns and Woodfield sites since the start of the replanting programme in 1998.
The wild wood is designed to attract plants - such as cowslips, bluebells, red campion and ragged robin - and birds and animals that have been lost to urbanisation back to the area.
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