Sugar Syrup Calculator
Work out water lbs and quarts for a batch of feeding syrup, 1:1 spring or 2:1 fall, from how much sugar you're using.
1:1 dissolves easily in hot tap water, stir until clear, then let it cool before feeding. Use plain white granulated sugar only. Skip raw or brown sugar (the extra minerals can stress bees) and never feed honey from an unknown hive, it can carry disease.
How it works
Feeding syrup is just sugar dissolved in water, but the ratio changes with the season. In spring, a 1:1 mix by weight is thin enough for bees to take up fast and use to stimulate brood rearing. In fall, a thicker 2:1 mix lets the colony convert it to capped stores with less work spent evaporating water out of it before cold weather sets in. The calculator takes how much sugar you're using, divides it by the ratio to get the water weight, then converts that weight to quarts using the fact that a quart of water weighs 2.086 lb.
Worked example: 10 lb of sugar in spring. At a 1:1 ratio, that's 10 lb of water too, which works out to 4.8 qt. Switch the same 10 lb of sugar to a fall batch and the ratio doubles to 2:1, so you only need 5 lb of water, or 2.4 qt. Same sugar, half the water, a noticeably thicker syrup that takes longer to mix but cures into stores faster once it's in the hive.
FAQ
Why does fall syrup need hotter water?
At a 2:1 ratio there's a lot of sugar packed into a little water, and it won't fully dissolve in water that's merely hot from the tap. Bring the water close to a boil, stir in the sugar until the solution runs clear with no grit at the bottom, then let it cool toward room temperature before you feed it. Hot syrup poured straight into a feeder can scald bees.
Can I use brown sugar, raw sugar, or honey instead?
Stick to plain white granulated sugar. Brown and raw sugars carry minerals and other compounds that can upset bee digestion in concentrated syrup. Feeding honey is riskier still, since honey from an unknown source (including store-bought) can carry spores that cause American foulbrood. The only honey that's safe to feed back is honey you know came from your own healthy hive.
How much syrup does one hive actually need?
It depends on what you're feeding for. A light spring boost might be a gallon or two over a few weeks to encourage buildup. A fall feed to fill out winter stores can run several gallons per hive, fed in rounds so the bees have time to cure and cap each batch before it gets too cold for them to process it.
What if my syrup goes cloudy or starts to ferment?
That's usually mold or wild yeast getting into a batch that sat too long, especially in warm weather. Don't feed it. Mix only what you'll use within a week or so, and keep any extra in a sealed container in a cool spot.
For more on when and how to feed, see feeding bees sugar syrup, fondant, and pollen patties and preparing your hive for winter. To check whether your colony has enough stores to begin with, use the winter stores calculator.