The chairman will be recruited from the industry and will work with the HTA executive board and directors.
Alex Vick is new executive director and runs HTA finance. The senior leadership team at the HTA comprises Vick, HR director Anne Clark, operations director Martin Simmons, and horticulture director Raoul Curtis-Machin.
Former HTA chief executive Carol Paris left for family reasons in April. She is set to return to the horticulture industry in a senior garden retail role this autumn.
HTA president Adam Wigglesworth, who has been performing some of the chief executive's role, said: "The board of the HTA has decided that the interests of the members are best served by appointing a professional chairman. He or she will be able to give the time and energy to ensuring that the strategic objectives of the Association are being achieved. In addition, the board will be expecting the chair to represent the HTA at a senior level to Government and other stakeholders.
"The Executive Team, headed by Alex Vick, are specialists in their areas, and I have no doubt that the individual, whether from the industry or not, will quickly be able to get up to speed on the significant issues for the members."
"The board will now commence a selection process with the aim of employing the new chair in the next 6 months."