I remember as a child finding a small shrub in our wooded backyard with perfectly circular holes cut into the leaves. The leaf had the appearance of Swiss cheese. I remember thinking that the holes were perhaps made by a hungry caterpillar or ant, but the perfectness of the holes was something that I remember to this day
After learning about leafcutter bees, I believe I may have found the creature who made those holes so long ago.
Since then, I’ve not seen a leaf with perfect holes like that time in the woods. I’m not sure if this is any comment on the decline in native bee populations, or if perhaps, I just don’t do as much looking at leaves now that I’m grown. But either way, I need a walk in the woods.
One of the best ways to ensure the success of each generation of new solitary bees is to take a hands-on approach. While native bees have everything they need to reproduce in the wild, there are some steps that we can do to ensure a higher hatch rate and healthier bees.
Storing your bees over winter
In the fall, the solitary queen is done tucking her brood in with their pollen loaf and nectar in their leafy blanket; the leafcutter bees will overwinter as a larva. It is now safe to handle the tubes and trays without disturbing the bees.
Remove the cavities filled with leafcutter cells from outdoors, and store in a cool, protected place over the winter.
Harvesting your leafcutter bees
Harvest your leafcutter bees in early spring.
Depending on the type of bee house you have, whether it’s trays or tubes, you need to carefully open the cavities, remove the leafcutter larva cells, break apart any large sections of connected cells and store the cells in a cool area in a fine mesh bag.
Crown Bees sells their Leaf Guardian Cocoon Bag which works perfectly for cocoon storage.
Incubate your bees
About a month before your garden blooms, it’s time to incubate your bees. The bees will naturally incubate once the temperatures reach 70 degrees. However, some people like to speed up the process and place their bees in a warm incubator set at 84 degrees. A room with a water heater or something similar will work as we
In this situation, your first male bee should emerge within 18 days.
On days 9-12 you may begin to see what appear to be tiny gnats emerge from the cells. These are a natural parasite that will re-enter the bee cells to lay eggs. These gnats should be squished.
After the first bee emerges, it is then safe to open the bag and place outside in your Mason/Leafcutter bee home. The rest of the bees will emerge within 1-2 days.
You can use the same house for mason bees and leafcutter bees. Mason bees will use 8 mm holes, where leafcutter prefer around 6 mm.
To learn more, check out my article Meet the Leafcutter Bee.