Foster Garden traces its history as a garden to 1853 when Queen Kalama leased a small plot of land to Dr. William J. Hillebrand, a German doctor with a love of botany. Botany was part of a young doctor’s training in those days. Queen Kalama was a member of the Kalakaua lineage and had received the land as part of the Great Mahele. Many of the tall trees in the garden today were planted by Dr. Hillebrand. He wrote “Flora of the Hawaiian Islands” towards the end of his life.

Later, Captain Thomas Foster and his wife Mary Robinson Foster purchased the parcel in 1880. They helped the garden to thrive. After becoming a widow, Mrs. Foster became interested in Buddhism and was very supportive of the Buddhist here in Hawai'i and also in Ceylon where she studied. As a thank you for her support, she was given a cutting from the Ficus Religiosa that the Buddha himself is said to have sat under. Mrs. Foster purchased other lands in the surrounding area and in 1916, a consulting botanist drew up an inventory of the plants in the garden. There was a total of 145 species of plants!

In 1919 Mrs. Foster leased two acres of land to the Hawai'i Sugar Planters Association for their experimental station. Dr. Harold L. Lyon was part of this work. Dr. Lyon and Joseph P. Rock identified the plants in the garden and turned the garden into a showplace! In 1925 the lease was extended for twelve more years.  A nursery was added where new plants raised to see if they could survive in Hawai'i, and to see if they could become a new crop for growers so there would be less dependency on sugar cane as a cash crop. The HSPA had contributed over 150,000 plants to this research. 

When Mrs. Foster died in 1930, she left her property to City of Honolulu with the stipulation that it should be named “Foster Park”. The Hawaiian Botanical Society stepped in and supported this Park becoming accepted as an asset to the community. The Park Board offered the HSPA the property and $2,000 a year for maintenance. In October 1931 this offer was accepted.  

Foster Garden was open to the public on November 30, 1931.  The beginnings of a world class orchid collection were started at that time also. Through the following years, the collection was documented and added to.

During the second World War, many air raid shelters were placed on the property. Work was done to formalize water rights, there being an ancient water way (awai) on the property. In 1952 The Garden Club of Honolulu proposed working on a hibiscus garden and an ornamental pool. These additions were presented to the City in 1957. The Outdoor Circle staffed an information station with their volunteer members. They also led tours, and school children learned a lot and then brought back their parents. Something that still happens! Dr. Lyon was working on a plan for a system of Botanical Gardens for the City and County. This would include, at that time, Wahiawa Garden and the Manoa Water Reserve. Paul R. Weissich was called on to develop this plan. This plan was approved in principle by the City Park Board.  

The shape of Foster Garden altered again with the development of the Lunalilo Highway and the widening of Vineyard Blvd. The shifting of properties in the area helped to form what is now the Foster Botanical Garden. The Garden Club of Honolulu and Outdoor Circle continued to provide volunteer support for the Garden. Since 1957 Paul Weissich had been assigned the duties and responsibilities formerly carried out by Dr Lyon. In 1961 Mr. Weissich became Director of the Botanical Gardens (Foster Garden and Liliuokalani Garden). In 1962 the Garden Club of Honolulu supported the concept of a “Pre Historic Glen”. This joined other star attractions, the Palm and Orchid collections. In 1961 a citizen’s group was formed called the “Friends of Foster Garden”. Today, Foster Garden is a first class Botanical Garden. The intentions of Mary Robinson Foster and other far sighted people are being carried out. Annual events in the garden include Plant Sales, The Mid-Summer Nights Gleam and an annual play named “the Beginnings of the Garden”. The Friends also support a Gift shop on Foster Garden.