Feeding Bees in the Fall: Why, When, and How to Feed Bees in Autumn
Honey production naturally slows down in the autumn. Most beekeepers harvest the honey crop and leave enough food stores for the bees during the coming months. But sometimes bees may have trouble building up their reserves. In this situation bees need a helping hand you will have to feed your bees in the fall. After all, the well-being of your valuable colony is at stake.
So how do you feed honey bees in the fall? First of all make an assessment whether your bees need feeding. The most common way to feed bees at this time of the year is with sugar syrup in a concentration of 2:1, two parts sugar to one part water. Use an internal hive top feeder and close up the entrance to protect the colony from potential robbing.
The methods of feeding bees are quite varied, and each has its benefits or drawbacks. Feeding in the autumn can be a useful management tool to prepare bees for the cold winter months ahead.
Feeding Bees in the Fall
Fall is a time of preparation for getting bees ready for winter. There are various reasons for feeding in the fall but mostly this is necessary due to a shortage of stored honey. Fall is a good time to judge the state of your colony and decide if supplemental feeding is needed to prevent your bees from starving. Without sufficient food stores, honey bees can easily die in a matter of days.
A miscalculation in the fall can lead to emergency winter feeding. On average a beehive should be left with as much as 60 lb (27 kg) of honey stores. This obviously depends on your climate, and could be less in warmer parts of the world, and more if you live in a cold region. A full medium frame from a super will contain about 5 lb (2.3 kg) of honey. There may be more in the brood frames but you need to estimate quantities carefully.
Honey stores may be low because of a period of long unfavorable weather. Bees can’t get out of the hive to forage and have to live on what they’ve got, using up precious stores and are unable to replenish them.
A nectar dearth is also another typical reason for low stores (a nectar dearth is a time when sources of nectar become scarce). This often happens at the change of seasons from summer to autumn when blooming vegetation begins to wane. Alternatively a drought caused by unusually high temperatures can mean that flowering plants die off. This leaves bees lacking nectar as they go into fall.
During a nectar dearth there can be an increased chance of robbing. Robbing situations can get very serious. It’s not good for your bees and it can be hazardous for your neighborhood. It’s the beekeeper's responsibility to prevent robbing in the first place. Feeding in the fall is one of the measures which helps avert this.
It’s also possible your colony got off to a late start and haven’t been able to store enough food for winter. A late growing population means bees have less time to forage.
Nature and circumstances don’t always work on the side of bees. But occasionally beekeepers remove too much honey when they harvest. Maybe you were over enthusiastic and removed too much by mistake. Alternatively it can be a choice of economics. If a beekeepers relies on the honey harvest financially, honey is harvested regardless of the level of stores, and replaced with cheaper supplemental feeding.
Most beekeepers recommend leaving sufficient honey stores so the bees can overwinter comfortably. But this is also a personal management choice for each beekeeper.
Whatever the reason for bees needing extra food, the most common way to feed bees at this time of year is sugar syrup. Feeding white sugar to honey bees is a beneficial management tool for beekeepers.
A secondary reason why beekeepers feed sugar syrup at this time of year is to treat nosema (bee dysentery). I’ve heard that the best way to deal with nosema is to prevent it occuring before it happens! Sugar syrup is used as the vehicle for preventative treatment of nosema.
When to Feed in the Autumn
Too much feeding can stimulate brood rearing. Especially when the feeding is done too early in the fall. That being said, I’ve heard of beekeepers waiting too late to feed and the bees have died! Don’t get too hung up on this, if you have a weak colony that needs to build up stores for the winter, a little extra brood is better than losing the colony.
The reason why brood rearing is not necessarily a good thing during the cold winter months, is because this has an effect on the amount of stores consumed by bees. Bees go into a winter cluster when the temperature drops. A colony with brood must keep the core temperature higher than if there was no brood (around 95° F/ 35° C with brood, and only 68° F/ 20° C without brood). Larger volumes of food stores will be required to maintain the higher temperature.
If you understand the nectar flow in your region then you have a better chance of judging when to feed (a nectar flow is the inverse situation to a nectar dearth). In some areas the nectar flow finishes early, with little chance of it returning. Bees coming out of summer will have larger colonies and a lot of mouths to feed. You can feed early in autumn in these kind of conditions. In other regions, wait until september, unless you think there’s a high chance of starvation.
What to Feed Bees at this Time of Year?
White sugar is the ideal source for producing sugar syrup for bees. The sugar content of nectar collected by bees while foraging is predominately sucrose. And white sugar is pure sucrose. So simple white table sugar is the source of food which is the closest to nectar.
Be careful what form of sugar you use. Organic sugar for example contains a very small quantity of ash which is less easily digested by bees. Brown and raw sugar contains varying quantities of molasses which is unsuitable to feed to bees. White sugar, also known as granulated sugar is the best source.
Some beekeepers prefer to feed bees with honey rather than sugar syrup. There is an argument that this is the “best” source of food for bees. The assumption is that the pH value of sugar (about 7) is neutral whereas the pH of honey is more acidic (between 3 and 4). This difference is said to be unsuitable for the bee’s digestive system. However, syrup is a supplement for nectar, not for honey. And nectar has a wide range of pH values (between 4.2 and 8.5 according to some studies). I don’t see any reasonable argument not to use white sugar to feed to bees. A good clean supply of sucrose will provide good wintering stores for your colony, and the least risk of digestive complaints such as nosema.
Before I get angry emails from disgruntled people who prefer to use honey, let’s look at a couple of other effects that feeding honey can have on a colony. Firstly, if you do choose to feed honey make absolutely sure that you’re using your own honey harvest and not honey from another apiary. Honey can contain a range of micobial diseases which would be transmitted to bees if fed infected honey. Also, feeding honey back to a colony can make them more aggressive. Furthermore, older honey has a higher level of the acid HMF which is toxic to bees. Finally, it seems that bees are more attracted to sugar syrup than they are to honey. Food for thought!
Admittedly, sugar is emergency food for bees and not really a substitute for the fabulous nutritional substances found in nectar. But if you find yourself in a sticky situation, feeding is essential for successful overwintering.
Note that the type of sugar syrup to feed bees in the autumn is not the same as you would use in the spring. Fall sugar syrup is thicker and is made to a ratio of 2:1 (2 parts sugar to 1 part water). In spring, beekeepers tend to use a more liquid mix with a ratio of equal parts sugar to water.
Spring sugar syrup is closer in consistency to nectar, whereas fall syrup resembles the consistency of honey. This distinction is important because weaker syrup has the effect of stimulating brood rearing, which is why it’s given in spring to get the colony expanding. Thicker syrup has the opposite effect. It gets inverted and stored in the comb, thus minimizing brood rearing.
Sugar syrup can be purchased ready-made, or you can make your own sugar syrup. It’s pretty simple to make by adding hot tap water to sugar and stirring (not boiling water). Some beekeepers also add essential oils to the mix which make it more attractive to the bees, and can be beneficial to the health of the hive. You can get a ready made product known as Honey-B-Healthy which includes these essential oils. Although it’s a little expensive, it is still an excellent product. It also helps prevent mold growth which can be a problem with simple sugar syrup.
How to feed bees in the fall
Feeding should take place after you have harvested the honey crop and the bees are still active.
Also, by removing honey supers before feeding syrup you won’t contaminate the honey with inverted syrup. Temperatures should be warm for feeding sugar syrup so that bees can easily move up to reach the feeder, invert the syrup and store it in the comb.
There are different types of feeders for providing sugar syrup. The best kind at this time of year would probably be some kind of internal hive top feeder which holds a large quantity of syrup. An internal feeder means the bees can get to the syrup even if the weather is bad. It also means the syrup is covered and is less likely to attract robbing bees from neighboring colonies.
A hive top feeder uses a series of inverted jars with small holes in the lids. Bees can drink the syrup without it dripping down into the hive. These can be placed directly over the top frames, or over the hole in the inner cover. For larger quantities of syrup you can even get 1 or 2 gallon buckets which work on the same principle. The syrup containers fit inside an empty hive box which protects them from the outside and allows the hive to be closed.
It is common practice to reduce the size of the entrance with an entrance reducer when you start feeding to help weak colonies fight off robbing bees.
When to stop feeding bees in autumn
Basically, as soon as bees stop taking feed then you can remove feeders from the hive. Check to see how the bees are feeding and when this slows down, remove the syrup.
However, be careful choosing this moment if temperatures begin to drop (especially below 40°F / 5°C). If this happens then you need to adjust your feeding strategy. If you’ve been feeding sugar syrup you should probably change to a hard form of sugar such as sugar candy or even dry granulated sugar. In colder temperatures bees have difficulty getting the water content in syrup to evaporate. So they’ll probably just ignore the syrup when it gets too cold.
Syrup needs to be checked from time to time to be sure it doesn’t ferment and go moldy. Syrup can grow mold in just a few days. Again, you can add essential oils such as spearmint and lemongrass which help inhibit mold growth, or alternatively add the ready-made mix Honey-B-Healthy.
If you leave a hive top feeder in the hive for too long it can increase the levels of moisture and it will eventually go moldy anyway. You don’t want mold lying around in the hive, so as soon as bees stop feeding, remove it.