There are classes for vegetables, flowers, fruit, floral art, arts and crafts, photography, cookery, preserves plus special classes for juniors.
A club spokesperson said: "The show is open to anyone and there are competitions for all ages and abilities, whether it's entering a photograph you've taken, baking a cake or showing your beans.
"Schedules and entry forms are available around town or can be downloaded from our website www.llangollengardeningclub.co.uk.
"The doors open at 1.00 pm (admission 50p - under 13 years free) when visitors can see which entries have been awarded prizes by the judges. There are also plants to buy, a raffle and refreshments. At 3 pm Dr Rhys Davies will be presenting the trophies.
"The committee would like to thank the many businesses in town which have kindly sponsored the show."