Did you water it thoroughly? ie really soak it?

Yep. though i usually didn’t water it very often pre-root prune, so perhaps i havent watered it enough since giving it a trim.

I've found that older Rosemary doen't do well with severe pruning.... unless they are use to it.... AKA: you do it all the time. You say it's been 3 years and that is a long time.

After being root pruned, repotted and cut back it will need much more watering than before. So don’t use your pre chop watering habits as a measure.

I've not found that old rosemary minds heavy pruning. But it will take longer to regrow from older wood.

And just for future reference, late spring - right when the plant is pushing major new growth - is the least desirable time of year to do repotting and root pruning. It places a severe shock on the plant (regardless of species, unless a summer dormant type). Late fall into winter is better and late winter into very early spring (before flowering) is even better.

As noted, a very thorough watering will help but it's going to take some time to recover.

May I piggyback onto this thread, since I have a related issue that doesn't really warrant a whole thread of its own? I just pruned a large rosemary yesterday and I'm not sure I did the right thing.

The rosemary has been growing in the ground in my greenhouse and at about 3 years old now, it has grown huge. It was over 6 feet tall, and sprawling 3 or more feet to each side, covering and crowding nearby plants. So I pruned out about half its volume yesterday, all from the sides where it was sprawling. I left the middle untouched, where it is standing over 6 feet tall against the wall. Can I prune it encouraging a few thick branches to become like tree trunks? Or should I trim it it down and encourage it to be bushy and shorter? Or is it not good to prune large rosemary so much?

I inherited a similarly sized one with my current garden. Lord knows how old it is - it has a trunk a good 3 inches in diameter and would tower over me if it didn't have a decided bend about half way up, either from some sort of earlier damage or just reaching for more light.

I prune the heck out of it a couple times a year.....just got done giving it a major haircut, taking maybe a third of it off. It always responds with a vigorous flush of new growth and I snip on that the rest of the year for cooking purposes. (I use the dried prunings in my barbeque)

@gardengal48 (PNW Z8/9) Thanks! I didn't know that about late winter. I'd heard that spring is a good time to prune. But then it flowered and went through a growth spurt. I wanted to wait for the growth spurt and flowering to finish before pruning. It seemed to be done by the time I did the prune. I'm in California, 9B.

You can prune any time you like - I take clippings from mine all year long. But something as radical as root pruning and repotting should be undertaken when it presents the least trauma to the plant and that is typically during dormancy or when the plant is not in active growth.

Thanks! Also, I've learned here that I've probably been underwatering it since the root prune/repotting. I was worried I was overwatering. I've read that when rosemary leaves go yellow, they will stay that way even if the plant recovers. Is that true?

Yes. A yellow leaf is dead. But all the advice about over watering refers to settled plants, not ones which have just been through the major trauma of losing a lot of roots and being required to start again in a new environment. Since you live somewhere where rosemary is winter hardy I wonder why you don't just plant it in the ground? It would be far easier to care for.

@floral_uk z.8/9 SW UK I can't plant it in the ground because I rent my home and my landlord would not want me to.

@ken_adrian Adrian MI cold Z5 Thanks for the advice. I can move it to shade until it recovers. It's very heavy. I had to move the pot anyway, which was why I did the root prune (it had grown through the pot and into the ground, so it lost a lot of roots just being pulled up from the ground.) I injured myself moving it, as it's that heavy. But I will try to get it into some shade, thanks.

I did do a significant trim to the top of it as well as I've read that you should do that when pruning the roots.

Photo:

Just to be on the safe side you could take cuttings. Have you already thrown out the trimmings? They’re easy and fast at this time of year. Just a few days to root. This one’s about ten days old.

Nice! i dried mine them for culinary use.

That’s an equally good use of the trimmings! 🙂

Nice looking lavender btw.