The Isabella Plantation is a 40-acre woodland garden set within a Victorian woodland plantation planted in the 1830s. First opened to the public in 1953, it is best known for its evergreen azaleas, which line the ponds and streams and at their peak of flower in late April and early May.
Article Source : https://www.royalparks.org.uk/parks/richmond-park/richmond-park-attractions/isabella-plantation