Wash and dry your mason jar.
Prepare the brine by dissolving the salt in the water. Note: You want to ensure your water is free from chlorine. Chlorinated water will slow or prevent the growth of the beneficial lacto-bacteria and yeasts.
Remove the greens and wash the radishes well. Cut the radishes into approximately 1/4 inch thick slices.
Pack the radishes and dill tightly into your jars and pour the brine over the radishes ensuring they are completely covered, leaving about one inch of headspace so your bottles don’t explode when the brine begins to bubble up.
Now, this is really important – the brine should cover the vegetables at all times or else they will start developing mould and your ferment may be ruined. So long as they remain under the anaerobic safety of the brine, they’ll be fine.
To keep the vegetables submerged, I placed an apple slice on top. You could also use a cabbage leaf or a piece of cheesecloth, for example, followed by some type of weight. Check out this post for some creative weight ideas. You can also buy fermentation weights.
Screw on the lids (but not too tightly in order to let some of the fermentation gasses escape) and set in a location at room temperature, out of direct sunlight. Soon you’ll see bubbles of carbon dioxide gas in the brine, which means you’ve been successful and the brine has started to acidify. This is the stage in which you will begin to “burp” your jar every couple of days if you are using a standard sealing lid. Simply unscrew the lid slightly and allow the gas to escape.
Over time, the mixture will become cloudy and reddened. Now, you can start to taste test the radishes.
But here is the tricky part. There doesn’t seem to be a cut and dry date for when fermented radishes are done. It seems to depend on the temperature of your home and how sour you like them. It should take 7 to 10 days.
Once the radishes are done to your liking, screw the lids on tight and place them in the fridge or other cold storage facility. You may also want to label your ferments with the date.