Guide to Mason Bee Keeping

Why Are Mason Bees Important?

Mason bees are essential pollinators for fruit trees, vegetables, and flowers. They collect pollen on their bellies (rather than their legs like honeybees), which results in more effective cross-pollination and higher crop yields. Because they are easy to keep and require minimal care, they are a great choice for gardeners and farmers looking to boost pollination.

Why Keep Mason Bees?

• Excellent Pollinators: They pollinate 95% of flowers they visit, compared to honeybees' 5%.

• Gentle & Non-Aggressive: Males don’t sting, and females sting only if handled roughly.

• Easy to Maintain: No hive inspections or honey harvesting.

• Boosts Garden & Orchard Health: Increases fruit and vegetable yields.

Getting Started

Choosing Mason Bees

• Common species: Blue Orchard Mason Bee (Osmia lignaria)

• Purchase cocoons from The Foraging Bee or attract local bees naturally.

Providing a Nesting Site

• Use bee houses with removable tubes or drilled wooden blocks (diameter: 5/16 inch, depth: 6 inches).

• Place in a dry, sheltered area facing morning sunlight (east/southeast).

• Ensure good airflow to prevent mold.

Providing Clay Mud

• Mason bees use mud to seal their nests.

• A small, moist patch of clay-rich soil near the house is essential.

Caring for Mason Bees

Release Bees in Spring

• Keep cocoons in the refrigerator (35-40°F) until spring (when daytime temps reach 55°F).

• Release near their nesting site.

Protecting from Pests & Predators

• Keep houses dry to prevent mold and parasites.

• Check for wasps or mites; clean and replace tubes if needed.

Harvesting & Storing Cocoons

• In late fall, remove cocoons and store them in a ventilated container in the fridge until next season.

• Clean nesting materials and replace as needed.

Common Issues & Solutions

1. Low Nesting Activity
   If mason bees are not using the house, it could be due to poor location, lack of mud, or cold temperatures. Ensure the bee house is placed in a sunny, sheltered spot and that moist, clay-rich soil is nearby. If temperatures are below 55°F (13°C), the bees may not be ready to emerge.

2. Moldy Cocoons
   Excess moisture and poor ventilation can lead to mold growth on cocoons. To prevent this, store cocoons in a ventilated container and keep the bee house in a dry, well-aerated area. Regularly inspect and clean the nesting materials.

3. Holes in Cocoons
   Small holes in cocoons indicate predation by wasps or birds. To protect them, cover the bee house with a fine mesh and ensure it is in a more sheltered, safe location.

4. Parasitic Mites
   If red mites are found on cocoons or inside nesting tubes, the nesting materials are likely contaminated. Replace nesting tubes annually and wash harvested cocoons in tepid water to remove mites. Keeping the house clean reduces the risk of infestation.

5. Cocoons Not Hatching
   If cocoons do not hatch, they may have been stored in conditions that were too cold or dry, or they may have been affected by mold or mites. Store them in a humid container inside the fridge (35-40°F) until spring. Before placing them outside, check for signs of damage.

6. Bees Emerging Too Early
   Warm indoor temperatures can cause bees to emerge before they are released. Keep cocoons in the refrigerator until outdoor temperatures consistently reach 55°F. When releasing, do so in the early morning to allow gradual warming.

7. Ant Infestation
   If ants invade the bee house, it may be placed too low or is attracting pests due to excess food sources. Mount the house at least 4-6 feet above the ground and use a non-toxic sticky barrier on the post to deter ants.

8. Wasp Infestation
   Wasps can take over mason bee nesting sites if the holes are too large or if wasp populations are high. Use tubes with a diameter of 5/16 inch to discourage wasps from nesting and monitor the area for any unwanted nests.

Additional Tips for Success

• Position the house facing east to catch morning sunlight.

• Clean and replace nesting tubes every year to prevent disease.

• Keep the surrounding environment pesticide-free to protect the bees.

Benefits to Your Garden

• Increased fruit and vegetable yield.

• Healthier flowers and plants.

• Support for native bee populations.

By providing a safe home and simple care, mason bees will thrive in your garden, helping your plants flourish!