Making summer or fall splits is very similar to spring splits, but with a few important differences. Regardless of where you are in the USA, it is ideal to split as early as possible in the summer. Many in the south wait until after they harvest honey (usually by July 4th), while northern beekeepers often split in July or August, during the honey flow. As a result, they sacrifice their honey crop, but hives tend to grow more quickly due to the abundant natural nectar and pollen flow.
The main goal is to split as early as possible in the summer thus ensuring more time for the split to grow before winter. To that end, I recommend splitting with a minimum of 4 frames of brood, covered with bees for summer splits. I also recommend using mated queens rather than queen cells for splits, and not allowing the hive to raise their own queen. You are in a race against the upcoming cold weather, and you need the hive to grow as quickly as possible. The most common reason I see for failure in making splits is letting the hive raise their own queen and not giving a split enough brood to grow quickly.
But, if all goes well, you should be able to add a second brood box to the split within 4 weeks. That second box should be filled within 4-6 weeks. Continuous feeding is essential in the south. In the north, it will vary based on the area. If bees are not bringing in large amounts of nectar & drawing out new comb, then feeding is needed.
Here's, step by step, how to make a summer split:
- Select strong hives with a minimum of 1 deep box full of bees (or its equivalent if using all medium boxes). Ensure they have at least 8 deep frames of brood, or their equivalent in medium frames of brood. 1 medium frame full of brood is equal to ⅔ of a deep frame of brood.
- Find the queen and set the frame she is on aside until step 5. If you plan to requeen, kill the queen after finding her. If you cannot find the queen, you have 2 options. The easiest is just to proceed with the split, ignore the queen, and go back and look at all the hives 3-4 days after moving the splits and see which hive has eggs. The hives that don’t have eggs need a queen.
Wipe out any queen cells present and install a queen. The second option is after you’ve completed steps 3 & 4, right before completing step 6, shake all the bees into the bottom box. The workers will migrate back up through the queen excluder, while the queen will be trapped in the bottom box.
- Leave 4 frames of brood and ideally 2 frames of honey in the bottom box. Fill the rest of the space with frames of empty comb, foundation, or frames of honey/pollen. If you have less than 2 frames of honey you can still split, but will need to feed immediately after step 8, and feed up to 2 gallons per week for the first few weeks.
- Do the exact same thing for the second deep box. If your hive was already a double deep hive, this is easy. Simply put 4 frames of brood & two frames of honey in the second deep. If it was a single story hive, you will need to have an extra box & frames to use. If it was a deep and medium, you can leave the medium box on the original hive. You will want to give the split at least 4 frames of brood and ensure the original hive has (between the deep box and medium) the equivalent of 4 deep frames of brood.
- If applicable, place the frame with the queen in the bottom box.
- Place a queen excluder on top of the original bottom brood box (Deep & medium hives - place the excluder on top of both boxes) and place your new deep split on top of the queen excluder.
- Replace the lid, and let the hive sit until dusk or dawn the following morning. If you didn’t kill the queen, the hive can be left in this configuration for several days if needed as you wait for the arrival of a new queen.
- At dusk or dawn pull the split off the original hive and put it on its own bottom board. Moving the split a mile or more away will ensure that all the foragers remain with the split since they will reorient to their new location. If you move them a few hundred feet or yards away, some of the foragers (usually less than 10% of the total population) may fly back to the original hive. There are a few alternatives to moving your split a mile away. You can rearrange the whole bee yard, so no hive is where it once was.
The foragers tend to drift back to all the hives fairly evenly. You can also move the original hive with the old queen 10-15 feet away and leave the new split in the original location. This will ensure the split has a bit higher bee population, since they will grow more slowly since they have to accept a new queen. The hive moved with the mother queen in it still has a laying queen and will rebound quickly.
- Feed both hives if there is not a strong natural flow. They have a lot of growing to do!
- Install the new queen ideally within 0-12 hours. If you wait more than 24 hours, you will need to remove any queen cells the bees have begun to raise.
- Continue feeding 1:1 syrup at approximately 1 gallon per week until the bottom box is 80% full of bees. When that has been achieved, add your second brood box & continue to feed until they have about 40 lbs of honey/syrup stored. This will take most hives until early/mid fall to accomplish.
Finally, don’t forget to control Varroa mites! They peak in the summer, and infested hives will have difficulty growing. If you are in a major drought or pollen dearth, you may also need to feed pollen substitute to help your splits grow quickly.