Warrnambool Botanic Gardens, set aside in 1866 and then developed according to a design of William Guilfoyle from 1877, is significant:
- as one of the most intact examples in Australia of a nineteenth century provincial botanic garden, a garden type best exemplified by the collection of such gardens created in colonial Victoria. Typical characteristics of provincial botanic gardens found at Warrnambool include a pinetum and windbreak plantings of conifers (particularly on exposed coastal sites), plantings of specimen trees,areas of intensive horticultural interest, and specialised plant environments (eg the fernery);
- as an expression of William Guilfoyle's design philosophy, his first known foray into provincial botanic gardens and exemplifying his ideas about picturesque sub-tropical gardens which were being actively implemented in his sweeping redevelopment of Mueller's design of Melbourne's botanic gardens;
- for its collection of plants, characteristic of late nineteenth century Victorian gardens as well as representative of more specialised plant groups (such as bamboos) befitting the scientific role of a botanic garden;
- for its retention of an important Edwardian bandstand;
- for the manner in which this site, located beyond the closely settled township area of the 1850s, enhanced the reputation of the northern area of Warrnambool and still forms a physical boundary to this late nineteenth century precinct.