I made a syrup with about three cups of sugar to one cup of water, boiled until clear, and hung a seeded skewer in a jar on the counter. Two weeks later there is maybe a centimetre of growth on the stick and a fuzzy white crust across the whole surface of the liquid and up the inside of the jar. The kids are losing interest. Is this timeline normal, and what is the fuzz?
Also check where the jar sits. A cold windowsill or a draughty spot makes the surface cool faster than the bulk and encourages exactly that top crust. Somewhere with a steady temperature away from the window is better, even if hiding it in a cupboard feels less scientific.
And do not move it or bump the counter. Every knock shakes crystals loose from the stick into the solution, where they become new seeds. We ended up putting ours on a shelf the kids could see but not reach, which solved both problems at once.
You can rescue this batch. Lift the stick out, break the crust, gently reheat the syrup until everything redissolves, add a bit more sugar since you have lost water to evaporation, cool to lukewarm and put the stick back. You lose two days and you keep the kids in the game.
Second this, and let them scrape the crust off the jar and eat it. It tastes fine, it just looks like frost instead of gems, and it stops the whole project feeling like a failure.
For the science part, tell them big crystals need slow growth and few starting points, and fuzzy crystals mean too many starting points at once. The same rule shows up in fudge, in honey going grainy, and in metals cooling. It is one of the more transferable kitchen lessons going.
@seasoned_saul · last yr.
Two weeks is slow but not abnormal, and the fuzz is your actual problem.
You have a supersaturated solution that would rather grow crystals anywhere than on your stick. Every dust speck, scratch and rough edge is a nucleation site competing with the skewer, and the crust across the top is thousands of tiny crystals winning that competition. Once the crust forms it also seals the surface and slows evaporation, which is why growth stalls.
For the next batch: use a more concentrated syrup, closer to 3.5 or 4 parts sugar to 1 part water by volume, fully dissolved at a low boil. Let it cool to lukewarm before lowering the stick in. Cover the jar with a paper towel and a rubber band instead of leaving it open. Use a clean smooth jar. Seed the stick by rolling a damp skewer in dry sugar and letting it dry hard for a few hours first, so it is the most attractive surface in the jar.
With that you should see obvious growth in three or four days and a decent stick in seven to ten.
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