How long to feed bees syrup in fall
Enter how much syrup the hive still needs, your feeder size and how fast your bees empty it. The page counts the refills, the days of feeding as a low and a high figure, and the date you would be done.
What the sources say
A University of Guelph transcript on feeding and overwintering has beekeeper Paul Kelly naming "about four imperial gallons per colony" of two to one sugar syrup. On feeders, he says a frame feeder holds about a gallon, so "you would need to fill it four times to get them through the fall." He adds that bees take down a hive-top feeder in "a week, four or five days," depending on the temperature.
Michigan State University Extension says to finish feeding by Oct. 1, with syrup at least 66%, which is 2 parts sugar to 1 part water. For a new package, it advises at least two deep frames of honey or 2 gallons of syrup.
An imperial gallon is about 20% larger than a US gallon, so four imperial gallons is nearly five US gallons. The page works in US gallons. Enter your feeder in US gallons too.
How the page works it out
In the pounds mode, the honey gap is multiplied by 1.05 lb of sugar per pound of stores, the same factor as the sugar to feed page. The syrup calculator then turns that sugar into gallons of 2:1 by weight. In the gallons mode, your figure is used as given. The gallons are divided by the feeder size and rounded up to whole refills.
Feeding days are the refills times your fastest and slowest uptake. The Guelph quote says "a week, four or five days", so I use 4 and 7 as the defaults for a hive-top feeder. It gives no figure for a one gallon frame feeder, and I have not found one, so for that feeder use your own observation. Refilling a feeder each time it empties is my assumption. In practice you may top it up sooner, which shortens the total.
The finish date, the weeks and the Oct 1 comparison are my own arithmetic on those inputs. Uptake changes with weather and colony size. Treat the range as a plan to adjust after the first refill, and check the feeder instead of trusting the calendar.
After the last refill
Weigh or heft the hive again and run the winter stores run-out estimate with the new weight. If syrup is no longer practical because of the cold, the candy board calculator covers solid sugar. This page covers feed amounts only and gives no advice on treatments.