Summer Leaf bees (aka Leafcutter bees) belong to the bee family Megachilidae, known as the architects of the bee world. Summer Leaf bees are famously known for cutting the leaves of plants to build protective walls and seal their nests. This unique behavior led to the common name: leafcutter bee.
Mason bees also belong to this family, but they use mud instead of leaves as their primary nest construction material.
In the summer, female Summer Leaf bees protect each nesting chamber with a protective shell of cut leaves and flower pieces. Because leaves are vital for keeping the developing bees safe, females will not nest if they do not have a reliable source nearby (within 30 sq. ft.).
Pro Tip: If you see neat, circular, or oval shapes cut in your leaves or flowers, they are likely created by Summer Leaf bees. You can quickly tell these cuts apart from caterpillars, which leave irregular-shaped holes!
What kind of leaves do Summer Leaf bees prefer?
Summer Leaf bees can use the leaves of almost any broadleaf deciduous plant to construct their nests. However, they prefer soft, flexible leaves and flower petals, such as alfalfa, clover, buckwheat, roses, peas, lamb’s quarters, lilac, redbud trees, or hostas.
There is no need to cut the leaves and bring them to the bees! Cut leaves will quickly wilt and do more harm to the plant than the minor cuts from a Summer Leaf bee. As long as there is a reliable source within 30 sq. ft., the bees will have no trouble finding and cutting what they need.
Important: Ensure that the plants in your area are free of pesticides and other chemicals, which have been proven to be toxic to bees and other pollinators.
Will Summer Leaf bees damage my plants?
Don't worry; the minor cuts the Summer Leaf bees make in the leaves DO NOT harm the plants! Bees and flowering plants have evolved together for millions of years! It's a mutual relationship, where the bees get food and nesting materials from the plant, and in return, the plant uses the bees to carry its pollen to other plants of the same species, or pollination!
Some people find the cuts unsightly to look at, but we prefer to think of them as evidence of pollination in action and a sign of a healthy ecosystem. Plus, it's a great conversation starter at your next BBQ!
How do I ensure my yard and garden have enough leaves for my Summer Leaf bees?
It's easy! A few leafy plants are plenty to support hundreds of nesting females.
1. Assess your existing leaf sources - take a look at the plants growing within about 30 sq. ft. of your bee house. Do these plants have soft, flexible leaves? Will these plants have leaves during the summer months when Summer Leaf bees will be nesting? If the answer is yes to both of those questions, you're ready for Summer Leaf bees!
2. If needed, plant easy-to-grow leaf sources - if leaves are missing from your yard and garden, add a few easy-to-grow plants near your bee house. We recommend planting native plants when possible because of the numerous benefits to our pollinators and ecosystems. Just remember to make sure they have soft, flexible leaves during the summer months when Summer Leaf bees will be nesting.
Summer Leaf bees will use a variety of soft, deciduous leaves to build their nests. However, we've included a list of plants that we've commonly noticed neat, circular cuts from Summer Leaf bees.
Note: While common and naturalized, some of these are not native to North America. Native species are bolded.
- Alfalfa
- Rose
- Lilac
- Asters
- Gaillardia
- Sunflowers
- Common Chokecherry
- Hosta
- Bougainvillea
- Peas
- Beans
- Oregon Grape
- Strawberry (smooth-leaved, not hairy)
- Field Pansies
- Buckwheat
- False indigo
- Lamb's quarters
- Redbud trees
- Hawthorn trees