Cetonia aurata
The Rose chafer is beautiful shiny green beetle found in the South of the UK. In some areas it is uncommon but in others can seen in healthy numbers quite regularly.
We started this breeding project in Summer 2025 with just one adult male and two adult females. We kept them in a deep terrarium in our garden with about 30cm of compressed heavily organic substrate. The adults are not too fussy and will lay eggs in any organic substrate providing it is moist enough.
After just three weeks we checked through the substrate and collected 18 eggs and 5 larvae. Due to the high heat of the Summer it was not advisable to keep them inside the terrarium outside. They are now housed in our garage to mimic more normal temperatures deeper in the soil.
We hope to continue to breed this species for conservation and aim to release adults in 2026 or Spring 2027 in various permitted sites across Cornwall and South Devon.
Our three adults continued to lay eggs in their outside terrarium in good numbers. We currently have around 40 L1 larvae which feed very well on fruit and vegetables near the surface of the substrate or buried below. It appears that raw compost material is preferred by these larvae to higher grade flake soil type substrates.
All our larvae have been housed communally in a 40L tub in the garage over Winter. This has meant we have been able to control the substrate temperature by naturally cooling it slowly but still keeping the temperature safely above freezing. When the temperature begins to rise again in the Spring we will add fresh fruit and new compost to encourage feeding and growth once more.
2026 updates:
From our 44 larvae with successfully hatched 39 adult beetles - an amazing success rate of 88% and far, far higher than what would be achieved in the wild. From these 39 beetles we intend to grow our breeding project so we can release more of these beautiful beetles into Cornwall and Devon.
To continue to breed this species over future generations we needed to keep a good number of adults for the projects. We divided the adults into the three categories below:
release 50% (20 beetles)
keep 23% for breeding (9 beetles)
Sell 27% at our Plymouth show (5 pairs)
With a higher number of adults retained in our breeding stock we intend to release a higher percentage next season to have a greater impact on local populations.
The first wave of beetles were released in July 2026 in some woodlands with open wildflower areas near our home. It was a joy to watch our captive bred beetles take flight into the wild.
