Hubbard introduced commercial biological control in the 1960s, building on his own experiments and with the help of the Lee Valley horticultural station.
His correspondence with Russian botanists led MI5 to briefly suspect him of spying after they mistook the use of horticultural terms for code.
Growing up at his family nursery in Essex, he entered the industry in 1948 at the age of 16 as a grower of salad crops.
Today, he owns Hill House Nurseries in Landscove, Devon, which he runs jointly with his son.
The firm crops more than 2,000 varieties of nursery stock and Hubbard has won acclaim as a breeder and plant finder. Notable achievements include Plectranthus ciliatus 'Sasha,' Phormium 'Lord Jersey,' Crocosmia 'Krakatoa,' Dianthus 'Old Mother Hubbard,' and Nemesia 'Bluebird', which has sold more than 11 million plants, bred under licence, worldwide.
During his 60-year career he has only been away from horticulture to complete his National Service, during which he built an English country garden for the officers' mess in the Egyptian Sahara Desert.
Another horticulturist celebrating a milestone is James Coles & Sons Nurseries chairman Geoffrey Coles, who has just turned 70.
He marked the occasion with family, who summoned him to the boardroom to enjoy a cake in the shape of a Coles lorry.
Coles has been chairman of the Leicestershire-based company since 1977 and has been responsible for the accounting and finance functions of the firm.
He is a past president of the HTA and winner of the Pearson Memorial Medal for exceptional and special contribution to the horticulture industry.
He has remained involved with industry councils throughout his career and has become a highly respected figure.
- In a week of significant anniversaries, Ransomes Jacobsen personal assistant to the managing director Dawn Gough is also celebrating - she has been with the company for 25 years.
Gough has held various roles during that time and, along with her current personal assistant duties, she is responsible for arranging European customer visits to the firm's Ipswich base.
In addition, since 2002, she has also regularly organised and attended the annual customer visit to the golf industry show in the US.