I always have more success rooting new sprigs that come out in the spring than old sprigs that have been around all summer. But I just stick them in moist soil with some rooting hormone. That tends to work.

Or, you might try pinning a branch to the ground and it will root from the Mother Plant. Then just cut off the newly rooted part and plant in soil. However, I doubt Rosemary will like living indoors over winter; but it never hurts to try.

I have read that rosemary actually relies on water absorbed from the air through its foliage. It likes humidity. So you might put plastic bags over the seedlings to keep the humidity high, until they get established. Also, misting indoor plants is a good idea, as it tends to be very dry indoors in the winter.

Not sure about the humidity part. My Rosemary grows really well here in the Central Valley of CA where humidity is very low.... and will dry quickly with no ground water. Having said that.... I also put a bag over a plant I’m trying to root to help with loss of moisture. But.... Rosemary can get moldy real fast if too much rain/wet, so.... who knows. I’ve always used the ‘peg method’ when rooting Rosemary.

It is very tricky to keep rosemary healthy or even alive indoors overwinter. Most herbs just do not fare at all well indoors regardless of how much light or dedicated care you can provide. And rosemary is very prone to fungal issues and mildew if kept too moist or humid so I would avoid bagging any cuttings and skip the misting. Contrary to common belief, misting dos not improve humidity indoors and typically leads to more problems than it solves.

This is also not a great time to take cuttings. Rosemary roots best with softwood cuttings, taken right after bloom or in spring or early summer. In addition to the wood being too ripe, there may not be sufficient time for the cuttings to root well and carry the plant through the trials of being indoors over winter. I'd suggest you take as many cuttings as you can manage to maximize your possibilities.

There is a mystique involved with growing herbs indoors and many websites make it out to be a lot simpler - and more successful - than it actually is. The reality is that plants that are hardy enough to grow outdoors in the northern hemisphere....and that includes even those that may be marginally hardy or not fully hardy in all areas......just make very poor choices as houseplants, even temporarily. Evergreen ones even more so than the deciduous ones.

Thank you. As I said, I had read that about rosemary and moisture in the air and leaves.

https://www.tenthacrefarm.com/growing-rosemary-indoors/

I saw that in this one source, and it did seem to be curious advice. The statement was that rosemary gets it's water through the air and not through it's roots. In general, bagging a cutting is smart. I do it for all my cuttings.

That being said, extension services recommend humidity for indoor rosemary, and misting as well.

https://extension.umd.edu/learn/rosemary-care-indoors

https://web.extension.illinois.edu/herbs/rosemary.cfm

Thanks for all the comments. It sounds like I may not be as successful at doing this as I would like.

I do lots of rosemary cuttings. For older sprigs, done as noted above, they are maybe half successful. For young sprigs, they are almost always successful. If I were you, I'd try to root a bunch of cuttings, and hope you get at least a successful one. I never do indoor rosemary, because the stuff handles our winters (temps almost always >20F, often never even freezing) just fine. I have large rosemary bushes outside.

There are a lot of web pages on how to do indoor rosemary (see a few above). I'd Google "rosemary" "indoor", and check them out. It's not easy, but it is possible.

And come back in spring and check on the Herb forum for questions about "what's wrong with my rosemary" :-) There are always many relating to attempting to overwinter indoors. Same with lavender indoors. Yes, it's possible.....just not at all easy.

Looking at the link it says Rosemary is accustomed to 'grabbing its moisture from the sea sprayed air.' This strikes me as counter intuitive to say the least. A. It doesn't necessarily grow by the sea in the wild and B. Sea spray is salty.

I have had great success with growing rosemary from seed, but only from Johnny's "primed rosemary seed." So Then I'll have one outside and try mulching it deeply in leaves to help it overwinter, but I'll also have one or more in pots to take in for the winter. My best has been one rosemary in the ground inside an unheated solar greenhouse that keeps things protected from the extreme minimum temperatures and cold winds.

After failing to keep my rosemarys (rosemaries?) alive inside in winter, I ordered a Madeleine Hill rosemary which is hardy to zone 6 to try this year. There are others hardy to zone 5, like Arp. My plan is to sink the pot and possibly bring it inside during deep freezes.

Yes, floral, that business about grabbing moisture from the air sounded a bit flaky. But it seems to be generally agreed-upon that rosemary likes some humidity. Too much, of course, will cause mildew. Low humidity is considered a likely cause of death for indoor rosemary. I have to suspect that mildew isn't as much of a risk for indoor plants, because the spores aren't there.

It thrives in my climate and there's plenty if humidity here. But it's not hot humidity. On the other hand it thrives around the Med where humidity is not high, in summer, at least. I've never experienced mildew on rosemary, even in the wettest weather.

I used to bring in a rosemary plant every Fall...it would lose a lot of its leaves but would generally hang on until the Spring when it would grow and thrive out on my deck. This year I bought a packet of seeds and started them indoors under lights. The plants did extremely well and I had numerous plants this summer for very little money.

Margi - Is your rosemary in a container? Is it Arp by chance? I've had good luck overwintering my Arp rosemary in a container in my minimally heated garage (it never gets below the upper 20s in the winter). I place it in a spot that gets some indirect sun and I water it lightly every few weeks. When we are having a mild day I'll place it outside for a few hours.

I don't bring it into the garage until we start getting down into the mid 20s consistently and then put it back outside around early March. Arp is hardy down to around 20F or maybe a bit colder in the ground but maybe not that cold in a container.

I started with a new plant this spring and It's currently in a 2 gallon container. I'll overwinter it in the current container and then pot it up to a 1/2 barrel in the spring after it starts showing new growth. Once I have it in the half barrel it is easy to pin branches down into the potting mix to propagate new plants like others mentioned.