A new affiliated membership category opens up the guild to horticulturists who are not professionally engaged in gardening.
Professional gardeners will no longer need five consecutive years of experience but can become members after completing five years at any point in their career.
The ratification of the changes at an AGM in North Wales last week brings to an end a long period of restructuring at PGG.
Chairman Tony Arnold said the moves should further open up the organisation to the wider horticulture industry. "Hopefully the changes will give us a [membership] boost. The five-year rule is especially important as many gardeners will change profession or take time out to have a family."
The affiliated membership category will be open to those working in professions related to horticulture, such as consultants and botanists, and those whose main source of income is not from gardening, such as garden writers and owners, designers, nurserymen and landscape architects and contractors.
The changes are the latest in a long history of moves to broaden the organisation's membership.
The AGM also made numerous changes to the committee. Arnold was re-elected as chairman for three years; Culzean Castle head gardener Susan Russell was elected as vice-chairman for Scotland, replacing Colin Totty, who stood down after 12 years; Margi Comeau was elected as secretary, replacing Sue Tasker; and Trevor Nicholson was re-elected as vice-chairman for the North and Wales.
The guild also voted to make president John Humphris the first lifetime member, in recognition of his work for the PGG and for winning the Victoria Medal of Honour.
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