2:1 or 1:1: Choosing the Right Autumn Syrup Ratio for Winter Stores
A practical breakdown of sugar syrup concentrations, fondant, and timing for autumn feeding, and why the ratio you choose signals different behaviour to the colony.
Concentration is a signal, not just a food source
Bees respond to sugar syrup concentration as more than a simple calorie source; the thickness of a syrup functions almost like a seasonal cue, influencing whether the colony behaves as though it is a time for growth or a time for storage. A thin, roughly equal-parts syrup (1:1, sugar to water by volume or weight) is close enough to a natural nectar flow that it tends to stimulate brood rearing and foraging-type activity, which is exactly why it suits early autumn buildup but becomes counterproductive later in the season when brood rearing needs to wind down rather than accelerate.
A thick syrup (2:1, sugar to water) behaves differently: its higher sugar concentration, around two-thirds sugar by weight compared to roughly half in a 1:1 mix, requires less processing effort from the colony to convert and store, and does not carry the same brood-stimulating signal. This makes it the preferred choice for the specific job of building winter stores efficiently in the weeks before temperatures drop too far for the colony to process syrup at all.
Timing the switch through autumn
Early autumn, roughly August into early September in most of the UK, is the window where a thinner 1:1 syrup earns its place, supporting the tail end of the colony's population buildup and helping ensure enough long-lived winter bees are reared before brood production naturally tapers off. Feeding heavy 2:1 syrup too early, while brood rearing is still an important priority, can push the colony toward storage behaviour before it has finished building the population it needs for winter.
From roughly mid-September through October, as temperatures cool and brood rearing declines on its own regardless of feed type, switching to 2:1 syrup shifts the priority toward rapid, efficient store-building before the weather turns too cold for bees to process and evaporate syrup effectively. Bees need a certain minimum temperature to fly, forage, and process incoming syrup, so this switch also needs to happen with enough time left in the season for the colony to actually convert and cap the fed syrup before temperatures drop too far for that work to continue.
Fondant and solid feed for the depths of winter
Once temperatures fall consistently below roughly ten degrees Celsius, liquid syrup of any concentration becomes impractical: bees cannot fly to forage it if placed outside the cluster, and processing wet feed inside a cold hive risks introducing excess moisture at exactly the time excess moisture is most dangerous to an overwintering colony. Solid feed, typically fondant at around eighty to eighty-five percent sugar concentration, solves this by requiring no evaporation and remaining accessible to a clustered colony without the same handling demands.
Fondant is placed directly above the winter cluster, close enough that bees can reach it without breaking cluster to travel any meaningful distance, and serves primarily as emergency or supplemental winter feed rather than the primary mechanism for building autumn stores, a job better done earlier with syrup while conditions still allow it. Checking stores through winter by hefting the hive, judging its weight, remains the simplest way to know whether fondant needs to be added, since visual inspection is limited once the colony is tightly clustered.
Working out roughly how much to feed
A commonly used rule of thumb is that a full-sized colony in the UK benefits from having somewhere in the region of eighteen to twenty-two kilograms of stores available for winter, though the exact figure depends on hive type, local climate, and how long the broodless winter period typically runs in a given area. Rather than trying to hit an exact number precisely, most beekeepers assess current stores by frame inspection or hefting, and feed the shortfall using 2:1 syrup while conditions still allow processing.
Mixing 2:1 syrup at home is simplest by weight: two kilograms of white granulated sugar dissolved into one litre of hot (not boiling) water produces a reasonably accurate 2:1 ratio, stirred until fully dissolved with no residual crystals, which matters because undissolved sugar can encourage fermentation in storage before the bees have a chance to process it. Feeding in the evening, using a feeder that minimises spillage and robbing risk, and checking uptake over the following days lets you judge whether the colony is processing syrup at a reasonable rate or whether cooler weather has already slowed things down more than expected.
Frequently Asked Questions
What happens if I feed 1:1 syrup too late into autumn?
Feeding a stimulative, brood-encouraging concentration too late can push the colony to keep rearing brood past the point where doing so is useful, consuming stores and colony energy on brood that may not mature into effective long-lived winter bees before cold weather arrives.
Can I just feed 2:1 syrup for the whole autumn feeding period?
You can, and some beekeepers do simplify this way, but doing so from very early autumn risks under-supporting the late buildup of the winter bee population that a period of 1:1 feeding is specifically meant to encourage, so many prefer the staged approach where practical.
Is fondant a substitute for proper autumn syrup feeding?
Not really; fondant is best treated as an emergency or supplemental feed for deep winter when liquid feeding is no longer practical, rather than the primary method for building the bulk of winter stores, which is more efficiently done with syrup earlier in the season.
How do I know if a colony has enough stores without opening the hive in cold weather?
Hefting, lifting one side of the hive slightly to judge its weight, is the standard non-invasive method used through winter, and with practice becomes a reasonably reliable way to judge whether stores are getting dangerously low without disturbing the cluster.