Hummingbird sugar water ratio

The scaling table

The ratio is by volume, not weight, and it does not need to be exact to the gram. Close to 4:1 is fine; wildly off is not.

Why four and not three

Four to one is roughly the sugar concentration of the flower nectar hummingbirds evolved on. That is the whole justification, and it is a good one — you are not trying to beat nature’s formulation, you are trying to match it closely enough that the birds get what they expect.

A stronger mix — 3:1 — is sometimes recommended for cold snaps or for fueling migration, on the theory that the birds need more energy. It is a genuinely debated point rather than a settled one, and there are two arguments against making it your default. A thicker solution is harder for a bird to draw up, and higher sugar concentration ferments no more slowly than 4:1 in warm weather while making the feeder stickier and more attractive to bees.

Our position: run 4:1 and do not overthink it. If you want to help birds through a cold snap, the higher-leverage move is keeping the feeder available — thawed, filled and clean — rather than changing the recipe.

Weaker is worse, not safer

A ratio like 5:1 or 6:1 is occasionally suggested as gentler. It is not. Hummingbirds are running one of the highest metabolisms of any vertebrate, and dilute nectar means a bird burns more energy visiting than it gains. If anything, the risk of accidental dilution is why a rained-into feeder should be emptied and refilled rather than topped up — see rain and feeders.

Which sugar

Plain refined white sugar. Not brown, not raw, not turbinado, not organic unrefined, not honey, not any artificial sweetener. Audubon’s recipe specifies refined white sugar, and honey specifically is warned against because it can promote dangerous fungal growth.

The full list of things people put in feeders that they should not is on what not to use.

The ratio is the easy part

Getting 4:1 right takes one measurement. Keeping that nectar safe takes a wash every few days for six months, and that is where feeders and people actually fail. Cornell’s guidance is every three to five days, daily in very hot weather.

If you want the full method rather than just the number, it is on the recipe page. If you want to know how often the whole thing needs washing, that is the cleaning cadence.