Cherishing Our Environment is the theme for this year's festival, which runs until November 22.
Held during spring when wild thyme colours the Central Otago hills purple and its aroma carries on the breeze, the festival comprises art and environment-based workshops, walks, markets, exhibitions, and competitions for all ages.
The Alexandra District Parents Centre held its annual teddy bears' picnic in conjunction with the carnival this year, as the first scheduled activity open to the public as part of the week-long event.
About 70 parents, caregivers, and children - predominantly from Alexandra and Clyde - attended the picnic at Molyneux Park with their teddies from 11am to 1pm.
Last night the festival was officially opened by organisers, who also opened an art exhibition to coincide with the event.
During the week local artists will be working in Pioneer Park, and on Saturday evening there will be a gala, at which Invercargill artist Russell Beck will unveil the 2009 community sculpture - his work titled Forces With The Dunstan.
A new event this year will be the cardboard boat race on the Manuherikia River from 5.20pm on Thursday.
Children will have the opportunity to get involved in the festival at school during the week, and participate in the Talent Thyme quest in Pioneer Park on Sunday.