@Bower Since I sort of hijacked that bay laurel thread talking about rosemary, I figured I'd start a thread on it!

That one of mine, that almost died from the 7° night I had, is Hill Hardy, which I got from Richter's herbs, and is supposed to be at least as cold hardy as Arp - a blue variety I tried long ago, but the flavor was different from regular RM, and I wasn't thrilled with it. It died from cold, after about 5 years, too, but I had already gone back to regular RM, which I had to cover, if it got bellow 20°. It died in January of 2018, and I only remember that because I was incapacitated, due to a knee injury and surgery, so I couldn't get out and cover the plants! In spring I got 3 of those Hill Hardy plants from Richter's, and a large leaf sage plant and some Syrian oregano (a.k.a. thyme scented) - some things I had years before, but the place I got it from didn't carry them anymore! Richter's has always been the best place for herbs, and the shipping wasn't bad, even getting things from Canada.

The Hill Hardy has the same flavor as regular RM, and another thing about it, that makes it grow faster is that it never flowers (same thing with that large leaf sage). I put 2 of those plants in the ground, and one in a 4 gal fabric pot, and the one in the pot grew faster. As always, when I'd try potted RM, the it got rootbound fairly quickly, though not as fast in the fabric pot, as in others even larger. Which is why I much prefer the ones in the ground! I kept that one in the pot on my back porch as the safety net, just in case. I also air layered one on one outside, just to see, and it worked great (the potted one is that one now), and also rooted some cuttings in the hydroponics, which worked quickly.

The trimmings when I re-potted them were more than half the plant, and a large part of the roots. Here's a photo showing the incredible growth on it 5 months after re-potting in April.
Hill Hardy Rosemary - 9-26, about 5 months after re-potting. by pepperhead212, on Flickr

And here's a photo of the RM and sage plants, in the ground for the first 3 seasons. The sage is cut back every year, and gets larger.
Sage, 4 ft across, and rosemary, almost 4 ft tall, that were dwarfed by that lemongrass! 10-30 by pepperhead212, on Flickr

And that lemongrass I was referring to, that I harvested just before that photo. I haven't grown any since then - it's all in vacuum bags in the freezer! I almost forgot how large that was.
4 lemongrass clusters, next to a large sage and rosemary plants. Ready to be harvested soon, 10-25 by pepperhead212, on Flickr

Soon I'll be transferring that rosemary in the pot into the ground, then I'll have to make a cutting or air layered one, to start a new pot!

Sorry for hijacking your bay laurel thread
That rosemary is amazing!!! and the others are lovely as well.
I look forward to seeing how often and how much you cut the rosemary back.
I also wonder if mine is the same variety. I don't remember where I got it, but I did get some plants as well as many seeds from Richters back in the day.

If your rosemary flowers, it's not the Hill Hardy. Sort of like tarragon - only from cuttings, and the like.

I had an Arp in the ground for a long time years ago but after I cut it back hard one time it declined a bunch and never recovered. The final nail in the coffin was a freeze and I had forgotten to cover it. I think I remember reading an article afterward that mentioned that rosemarys don't like a lot of pruning but yours seems to be doing great!

Then I had a Tuscan Blue which I planted outside the back door, not down in the garden. It thrived for years and eventually died of old age but not before I took cuttings and started a new one. That one has been in a large pot on the porch for about four years now, never repotted but I really should do that after taking more cuttings "just in case".

I bring the TB indoors on nights when it's supposed to get below 30 just as a precaution.

Today I dug up that old rosemary, and planted the potted one I've had over 2 years in a 6 gal (I thought it was 4 gal) fabric pot, and it was totally rootbound. I cut probably about 2/3 of the roots off with a knife, before planting it, with some worm castings (saw a bunch of worms when I dug everything up, which is always good) and some of that soil out of the pot, I sifted most of the roots out of. I also replaced the mulch fabric, since I had to cut it up a lot, to get the plants out. And that fabric is 4' across, for a size reference.
Replaced the rosemary in the ground with the potted one, which was solid roots! by pepperhead212, on Flickr

Before doing this, I got almost 5 more gallons of soil mix ready for starting seeds - some used briefly, but the plants died, since it was too cold for it. I just sifted that, and some other soil mix I didn't heat, the first time. This time, instead of inside the indoor oven, like the first 3 gal batch I heated, to sterilize, I put the foil roasters with the soil in them on my outside grill, on low, and left them there, while I was outside, and eventually turned it off. Tomorrow I'll add the micorrhyzae and the Bt israelensis, like before, and get it ready for any seed starting, that is happening soon.

pepperhead212 wrote: ↑Wed Mar 22, 2023 6:54 pm Today I dug up that old rosemary, and planted the potted one I've had over 2 years in a 6 gal (I thought it was 4 gal) fabric pot, and it was totally r

Before doing this, I got almost 5 more gallons of soil mix ready for starting seeds - some used briefly, but the plants died, since it was too cold for it. I just sifted that, and some other soil mix I didn't heat, the first time. This time, instead of inside the indoor oven, like the first 3 gal batch I heated, to sterilize, I put the foil roasters with the soil in them on my outside grill, on low, and left them there, while I was outside, and eventually turned it off. Tomorrow I'll add the micorrhyzae and the Bt israelensis, like before, and get it ready for any seed starting, that is happening soon.

Do you think using a griddle would work for sterilizing medium? If I put it in foil roasters and set it on top of the blackstone grill surface? How hot does it need to get to? I have a lid so I can keep the heat inside it like an oven.

Thanks for sharing! I picked up a Hill’s Hardy (read on houzz that there is controversy about that name, ha! There’s always drama on houzz) plant a few weeks ago, looking forward to planting it out soon.

@Rockporter
I just close it up, and let the temp get to 200°, or a little over. I just put one of those quick thermometers in after an hour or so - takes a while if it's moist. I kept only 2 of the 4 burners on, and on just above minimum - on the lowest, it was down at 180°.

pepperhead212 wrote: ↑Wed Mar 22, 2023 7:58 pm @Rockporter
I just close it up, and let the temp get to 200°, or a little over. I just put one of those quick thermometers in after an hour or so - takes a while if it's moist. I kept only 2 of the 4 burners on, and on just above minimum - on the lowest, it was down at 180°.

Oh that is a good idea to keep only two burners on, that way I am not actually setting the pan onto a hot griddle. It might get warm under it but it shouldn't get too hot. Thanks, I will try that.