This Is How Long It Takes Bees to Fill a Brood Box

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One of the first questions new beekeepers ask is how long it will take their bees to fill the frame of their brood box. Many experts and bee enthusiasts say different time scales to one another, and it can be difficult to choose who to believe. But, how long does it take for bees to fill a brood box?  

Many factors can widely change how long it takes bees to fill a brood box. In the ideal world, it’ll take around two to three weeks. However, it can be longer or shorter in some cases, depending on the hive strength and nectar availability/quality.

As you can see, it’s tough to pinpoint exactly how long it’ll take for bees to fill a brood box. However, let’s take a look at the factors involved in how long this takes, so you’re able to visualize a better timeframe.

How long does it take bees to fill a brood box?

For bees to be able to fill their brood box, the most important thing is that they’re able to produce excess honey. They’ll need this excess honey to feed the extra bees. Two main factors are going to influence this.

1. Hive strength

The hive needs to fill several requirements before the bees in it can fill it with more bees. Whether you start with a nucleus hive, a swarm or package is essential to allow the bees to begin building their numbers. For a hive to function properly, it must have bees at all stages of life; eggs, larvae, and capped brood. Bees do different jobs at different ages, so you need all stages of the bee life cycle to have the hive performing at full capacity. The queen needs to be young and vigorous, laying eggs as fast as she can. The hive needs to be free of diseases like chalkbrood and foulbrood.

2. Nectar availability and quality

This is where the conditions of your local environment will come into play. As I said, bees need to be able to produce excess honey to expand their colony. Honey is a foodstuff for the bees, so they need something to feed the extra bees on. They produce honey via nectar from flowers. So, naturally, how much honey they can produce depends on the availability of a good nectar flow. You’ll need to take notice of the seasons and the types of flowers available in your area. The best practice is to grow as many as you can in your garden.

Nectar flow in many parts of the world is predictable and regular, but in some places, it isn’t. Join a local beekeeping community to find resources on tracking these sorts of things and what might be the best flower to plant in your garden.

There are many signs of a good nectar flow in the area. The simplest is just looking for flowers in the area, seeing if flowering trees and plants are widespread. You’ll also notice increased activity in your hive, with lots of bees coming and going during the day. Bees landing at the entrance will have abdomens visibly full of nectar. You’ll even be able to smell the nectar ripening on warm nights and shake it out of uncapped frames. Finally, the hive will increase in weight, which you can check by lifting the back of the colony.

When should I add another brood box to my hive?

As the brood continues to develop, the bees will start wanting to build up honey reserves for winter. Brood boxes will contain a mixture of honey, brood and pollen. Whereas upper boxes that you add later will be used more or less solely for honey. You’ll need to add boxes to make sure they have space for honey and brood. Furthermore, bees without enough space could even begin swarming, which can be very difficult to remedy.

The answer will, again, depend on your particular conditions. In ideal conditions, your bee colony will expand very rapidly, and you’ll start to notice their frames filling up very quickly. In your hive box, the bees will create comb out and then up from the center. The queen will begin laying from the center of the hive outwards until all the frames are filled.

When to add more boxes

You will need to keep a close eye on the frames to know when to add more brood boxes. Don’t wait until every frame has drawn comb. In a 10-frame box, wait until 6-7 of the frames are filled with comb and consider adding more. The bees will continue working outwards into the frames they have but will now be able to expand upwards as well. There is some debate about exactly when is the best time to add the extra brood boxes.

You need to keep in mind that you can’t just add them at the beginning. Many do ask why you wouldn’t simply add them at the beginning so the bees can expand as they need to. The fact is, too much space can be a problem for the bees. Too much space can leave them cold even on summer nights, and pests and insects are more likely to find their way into the empty spaces in the box.

So, it would help if you didn’t start with more space than your bees need. With that in mind, we think it’s best to add extra boxes once your bees have filled about 6-7 frames, as this marks a good mid-point. Some say you can add extras at five full frames, and some as late as 8. Doubtless, many bee colonies would thrive under these conditions, but the variation is so great between conditions than 6-7 frames as a midpoint seems like a good rule of thumb that you can adapt to your conditions.

Single brood box

Finally, there is a question among beekeepers about how many boxes to dedicate to brood. You can use a device known as a queen excluder to restrict the queen, and consequently the egg-laying, to a single box. Some beekeepers believe this to be worthwhile, but it will restrict the size of your colony. As long as you keep a close eye on how the colony develops, adding brood boxes at the right moment won’t be difficult.


After reading the above, you should know how long it takes for bees to fill a brood box. As discussed, this is very hard to determine because it depends on how well the hive is performing with its reproduction and production processes.

About Grampa Beekeeper

Having spent a lifetime tending to bees, I now want to pass my knowledge onto the next generation of beekeepers. Beekeeping may not be fashionable, but it is my life long passion! From entrance excluders to packaged bee handling, I've got you covered! I'm not the best at writing, though, so bear with me!!