Herb Cuttings Smell Bad

Have you ever tried rooting herbs in a glass of water? I've tried it with a good number of herbs: sweet basil, cinnamon basil, Thai basil, Swiss mint, chocolate mint, Japanese mint, lemon mint, tarragon, rosemary, stevia, lavender, cat's whiskers and some others.

In some cases, it would work. When it does work, I would usually see roots within a week. I don't usually remove a lot of the leaves (you'd usually read something like retain only the top four leaves) so the cuttings generally wilt for a few days without perking up.

If it's been a couple of days and the leaves look fresh, those cuttings will probably root.

In some cases, the leaves start to look wilted or just dry. Chances are, that will not root.

However, in my experience, I found that there's another indicator. If the glass of water starts to smell rotten, those cuttings will probably not root. If I had to guess, I think the oxygen gets used up and the water becomes anaerobic. The cuttings thus die and the anaerobic bacteria makes the water smell.

I have not perfected rooting cuttings of herbs by any means, but I may have a few useful "tips". I once bought a pack of basil from the supermarket. I had so many to root! I crammed them all into one glass. Bad mistake. Within a day, it started to smell. None of those cuttings survived. Perhaps the chances of the cutting surviving will be more if you stick to few cuttings in a glass.

I also think changing the water helps. These days, I change the water everyday. I just use the "spent" water on plants in soil so I don't waste anything. Change it everyday and it won't smell. I also try to put enough water per glass (about 1/4 cup)

As for sun exposure, I'm not sure what's better for cuttings. These days, I'm leaning towards leaving cuttings in partial sun only since they don't have roots and thus have limited ability to absorb water. But I don't really know.

Finally, I've also tried adding a little amount of vermicast in my cuttings in water.  I'm not sure if they're helping though.  I haven't really "tested" it but psychologically I guess it helps me.

Any similar experiences or insights?

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