Coley left on 30 October to lead a conservation start-up in Wales. Tina Houlton is acting as interim public programmes director but according to the consultation the post will not be retained.
Head of library, art and archives Christopher Mills has also resigned, with Fiona Ainsworth acting as head of department at present. Head of communications and marketing Bronwyn Friedlander has also left to work for the Royal Society.
Kew said it is taking the opportunity to restructure and seek efficiencies, initially raising fears that further jobs were on the line. However, a staff consultation document seen by Horticulture Week suggests that those most likely to be affected are in upper management, with the restructure expected to save just £100,000.
Among possible restructuring options, the library, art and archives collection was set to move to either corporate services or to the science department, where it would report to head of collections. The consultation document says the collection has "synergies" with both science and information services.
Gallery operations were to move to horticulture and operations "to improve co-ordination across the site, ensure consistency and follow through at all levels, identify synergies and capture efficiencies", according to the consultation document. A number of other changes to reporting lines are also being made, including adult education, creative development and design and production.
An RBG, Kew visitor group is also being created to develop and oversee the visitor offer at both Kew and Wakehurst Place. Members include horticulture director Richard Barley, science director Kathy Willis, Wakehurst Place director Tony Sweeney and Kew's executive director Richard Deverell.
It will meet monthly and approve all events, festivals and strategic decisions that are "visitor-facing" as well as monitoring performance. The new structure is planned to go live in the week commencing 7 December.