Nine times out of ten a wine that is not bubbling is either too cold, has not been given long enough, or is fermenting perfectly well while the gas escapes past a badly seated airlock. The first thing to do is not to add anything: it is to check the temperature, because wine yeast is happiest between 22 and 27 degrees Celsius and sulks below that. If the wine is warm, sealed and genuinely still, then it is time to work through the other causes. This is the troubleshooting order we would use on a batch made with our Hedgerow Wine Making Kit, from the most likely cause to the least.
First, is it actually not fermenting?
An airlock is a gas escape valve, not a fermentation meter. If the bung is not pushed firmly home, or the grommet in a bucket lid is not seated properly, the carbon dioxide takes the easier route out around the seal and the airlock sits there doing nothing while the wine ferments away happily.
So look at the wine itself rather than the airlock. Real signs of fermentation are a foaming cap or a fine rim of bubbles on the surface, a faint hiss if you put your ear close, tiny bubbles rising through the liquid, and a smell of bread and fruit rather than nothing at all. Push the bung down firmly, check the airlock is filled to the halfway mark with water, and give it an hour.
Second, is it warm enough?
This is the single most common cause, especially for anyone starting a batch in October or November. Fermentation needs warmth and hates cold draughts. A garage, a conservatory, an unheated back porch or a cold windowsill will all slow a wine to a crawl or stop it entirely.
Find somewhere with a steady temperature between 22 and 27 degrees Celsius, out of direct sunlight: an airing cupboard, a warm corner of the kitchen, a shelf near a radiator but not against it. Do not obsess about the exact number, because steadiness matters more than precision, but do move it. A stick-on brewing thermometer costs very little and saves a lot of guessing.
If the wine has been cold, warming it up is often all it takes. Give it a day or two at the new temperature before you decide anything has gone wrong.
Third, has it simply not started yet?
Yeast has a lag phase. It needs a few hours to rehydrate, wake up and multiply before there are enough cells to produce visible gas, and in a cool room that can stretch to a day or two. Beginners routinely declare a batch dead at the twelve hour mark.
While you are waiting, check the obvious. Was the yeast actually added? Was the liquid too hot when it went in, which kills yeast, or too cold, which stalls it? Frozen fruit is a classic culprit here: it needs to be defrosted thoroughly and brought up to room temperature first, or the whole brew is chilled below the point where anything will start.
Canned fruit is worth a mention too. We would not use it, partly because the flavour disappoints and the syrup makes sugar levels hard to judge, but mainly because many brands contain preservatives that stop the yeast fermenting at all.
Fourth, is there a problem with the sugar?
Two opposite problems live here. The first is sugar that never dissolved and is sitting in a layer at the bottom of the bucket. Give the mixture a good stir to dissolve it, then allow a day or two before straining out the fruit. No harm done.
The second is too much sugar. If a great deal went in, the yeast can reach its maximum alcohol tolerance, somewhere around 13 to 14 per cent, before the sugar runs out, and it stops with the wine still sweet. A hydrometer reading is the only way to confirm this. Only artificial sweeteners are a lost cause, because yeast cannot ferment them at all and needs real sugar to make alcohol.
Underfeeding is the other side of the same coin. Country wine is fruit, sugar and water, which is a thin diet, so the yeast nutrient in the kit is not optional garnish. A batch that started well and then went sluggish is often a batch that ran short of nutrient.
How do you restart a stuck fermentation?
In this order, giving each step a day or two before moving on.
- Warm it up and be patient. Most stalls solve themselves here.
- Rouse it gently. A careful stir puts settled yeast back into suspension and gets it working again.
- Add yeast nutrient as the recipe book directs, if the fermentation began well and then faded.
- Pitch a yeast starter. Empty the yeast into 50ml of warm water and leave it five minutes. Dissolve a teaspoon of sugar in 75ml of warm water and add it. Cover it and leave it somewhere warm and dark for three to four hours, until the liquid turns cloudy and foam gathers on top, then add it to the fermentation vessel. A starter that is already active stands a far better chance than dry yeast tipped into a cold, half-fermented wine.
And the opposite problem: still bubbling after three weeks
Let it finish, however long it takes. A slow fermentation is not a fault, and country wines often take their time. Bottling before fermentation has completely stopped risks an over-sweet wine at best and burst bottles at worst.
The test is simple: the airlock has gone quiet and stays quiet. If the wine has also cleared and fermentation has genuinely stopped, you are fine to move straight on to the next stage, even if that is earlier than the recipe suggested. A batch takes eight to twelve weeks from start to glass, and the waiting is most of it.
The kit contains wine yeast, yeast nutrient, pectolase, finings, citric acid, a stabiliser tablet and a steriliser (sodium metabisulphite), with the recipe table. You add the fruit, sugar and water, plus a bucket, a demijohn or second bucket with an airlock, a siphon and bottles. The allergen line is contains sulphur dioxide and sulphites, every ingredient is listed on the pack, and if you have an allergy question, email hello@sandyleaffarm.com before ordering. Wine making is for adults aged 18 and over.
Stuck fermentation FAQs
How long before I should worry that my wine is not fermenting?
Give it a day or two at the right temperature before doing anything. Yeast needs time to wake up and multiply, and a cool room can stretch that out considerably.
My airlock is not bubbling but the wine looks active. Is that a problem?
No, it usually means gas is escaping around a loose bung or grommet rather than through the airlock. Push the seal home firmly and check the airlock is filled to the halfway line with water.
What temperature does wine yeast need?
Between 22 and 27 degrees Celsius is where it is happiest. Steadiness matters more than hitting an exact number, so avoid cold draughts, unheated garages and direct sunlight.
Can I add more yeast to restart a stuck wine?
Yes, but make a yeast starter first rather than tipping dry yeast in. Warming the wine and rousing the sediment are worth trying before you reach for more yeast.
My wine is still fermenting after three weeks, should I bottle it?
No. Wait until the airlock has gone quiet and stays quiet, because bottling an active wine risks burst bottles. Our hedgerow wine kit works on an eight to twelve week timescale, and longer does no harm.
Ready to start a batch that behaves? Have a look at our wine making kits.
