Harvesting leafcutter bee cocoons

 We’ve had a great summer, what do I need to know about harvesting my cocoons?

Towards the end of March, early-April, your cocoons will be ready for harvest. Harvesting is really important in the overall process and there really isn’t a great deal to it. You will need to put aside an hour of your day to complete this process.

The primary reason for harvesting is to prevent any pest build up. These bees will use cavities, will use the holes you provide with your leafcutter bee house, and next season’s dormant cocoons should be the end result.

While using holes drilled in a block of wood would equally provide the same cavities, the inflexible nature of the wood forms nesting materials that can’t be taken apart. Effectively over a course of time, you will get pests building up in those holes and overall, you will end up with a leafcutter bee graveyard.

The nesting material we provide are laminated nesting trays that easily come apart for you to harvest these cocoons with little issue and ensure the future population of leafcutter bees continues to rise.

Leafcutter bee harvesting

 I’ve got more cocoons that I first started with, what should I do?

Great stuff, your house has provided an excellent nesting habitat through summer. Starting off with a set number of cocoons (50-75), the aim is to increase these numbers by the end of the season. At the completion of the season, typically late March, early-April, bring your house back in for harvesting.

Open the laminated trays, and with a lolly stick or a pencil, gently push the cocoons out, pop them into the pot they first came in, or a similar type of plastic pottle and then place them in your refrigerator. They will need to be refrigerated at the normal domestic refrigerator temperature.

This ensures full eradication of the one little pest that can affect the leafcutter bee in New Zealand – the little parasitoid just a millimetre in diameter and can only be seen through a microscope lens. By refrigerating these dormant cocoons, the temperature will naturally eradicate any presence of this pest and will ensure your cocoons are ready to be placed out again next spring ready to commence the process once again.

 As my cocoon numbers grow, should I consider adding more habitats in my garden?

As a rule of thumb, most gardeners will start off with one Leafcutter Bee House and a set number of cocoons – likely to be between 50 or 100. Ideally, it is recommended to have one hole available for each cocoon, with the bee house designed to accommodate up to 100 cocoons.

As your numbers increase, in some cases it is possible for them to double – it is strongly encouraged to add additional houses to your garden to support those numbers for the following year.