11

Cut off all dead wood at the base, leaving just the live stems - you don't need to do anything to the roots. You might, though, want to consider replacing the plant - it'll look pretty ugly once the dead stuff has been removed. This plant doesn't regenerate from old wood, so you won't get any new growth other than on the two existing live stems.


6

It does look like powdery mildew, but ensure they get plenty of sunlight, so if they're not in a sunny spot, move them if possible. Try the milk treatment - 1 to 3 parts cow's milk mixed in a sprayer, spray all parts of the plant, including under the leaves, until run off. Repeat after two or three days if necessary - works best in bright light or in ...


6

There's a type of ladybug that specializes in spider mite control. It's called a spider mite destroyer lady beetle, or Stethorus picipes. They work well, but regular ladybugs just fly off. However, they weren't the most thorough, so I usually use neem oil, or insecticidal soap. Soap and water is very effective, but more damaging to the plant, than neem oil,...


6

It is a fungus digesting the organic matter in the soil underneath the plant, and it is, if anything, beneficial. See the bark chips in the soil? They are what the fungus is breaking down. The white stuff you saw under the surface is mycelia. The part on the top is the reproductive material. It really only eats the undecomposed material, rendering it into ...


5

You can: cut off the live branches and root them (put the base in water until roots come out) remove the rest of the plant plant the newly rooted branches where the old plant was.


4

Do you not suffer with Rosemary Beetle (Chrysolina americana) in San Francisco? Maybe not, we have it here in the UK. Otherwise, just a word about Rosemary Oil - it's expensive because it's difficult to produce without it being infected with botulism, but even if you found a cheap source, it's unlikely to work on whatever pest is troubling your plant ...


4

While I am not intimately familiar with rosemary per se indoors in Colorado, I am aware that many plants are remarkably sensitive to humidity and this comes up particularly with plants like ginger (which I have grown indoors in central Utah as a kid). The first thing I would do is assume that the problems may be related to a drop in humidity and ...


4

Check the plants carefully, examining them closely to make sure there is no evidence of spider mite (webbing, tiny red or brownish insects). Assuming there isn't anything to find, you've said the plants in the photographs are 4-5 years old, and you have two other plants which are only 2 years old which are fine. If the 4-5 years old plants which are showing ...


4

It looks more like a young Helichrysum italicum than Rosemary, but since that's the curry plant, meaning it smells of curry when you bruise the leaves, it shouldn't be hard to tell. It's not toxic to eat, but does not impart a curry flavour to food - the flowers are yellow, and the oil from those is used as a herbal remedy for various things.


4

Looks like Fuligo septica, one of the slime moulds, also known charmingly as dog vomit slime mould. Harmless, but not attractive, and very common where there are bark chips within the compost mix or on top of the soil. Allowing it to dry out between waterings might help a bit, but you might find it returns, so if it does and you really hate it, you may need ...


4

Rosemary looks over watered, you are correct that the roots may have some rot. They are great at being "left alone". If you are leaving them alone, sometimes the use of gardening soil instead or potting soil OR packing the soil too tightly can cause the pot to store too much water. IF you used potting soil, consider replanting it and packing the soil a tad ...


4

I think what you are seeing are random weeds that are sprouting in your pot from air blown seeds.


3

Most likely leafhopper damage, specifically what's known as Sage and Ligurian Leafhoppers - they're usually under the leaves, small and unless you look closely, you may not actually see them. It isn't just rosemary that's affected, other aromatic/herb plants in the Lamiaceae family are subject to the same thing, plants like sage, lavender, mint and so on. ...


3

Sand arrives at playgrounds already full of dirt - ours always had clay in it, which is terrible for drainage - only thing it would have grown was dirty clothes. .... If you want to grow in sandy medium, go to the hardware or home store and get a little bag of cactus soil. It does really drain! If it has to be sterile, spread in a pan and bake in the ...


3

Looks like a case of poor drainage to me, coupled with your moving it into and out of the house, as Bamboo noted. If you bought it at Lowe's, did you repot it? I've grown rosemary indoors in a heated room for something like 20 years now, with very little direct sunlight (east windows only). I've lost a few over the years, with only one of my deceased ...


3

Rosemary is hardy down to between -10 to - 05 deg.C; in a pot, its a bit more vulnerable, so -5 C is probably best. That is around 23 deg F,though shortlived exposure to 14 deg F would be fine. Every time you lift it into a heated environment, then put it back outside, then bring it in again, it suffers transition shock. These plants do not do well for any ...


3

I'm wondering where you are in the world for one thing, but Rosemary is a mediterranean plant used to growing on dry, impoverished soils. It's not too keen on over fertilised environments, so that might well be the cause of the problem. I note you mention poulty manure - if this was pelleted or neat, it needs to be 'slacked' before use if you're applying to ...


3

I used to grow rosemary and they need moving air just as much they need sun and water. That's why it may be difficult to grow indoors.


3

Scienctific aspects aside, just some practical advice: If I were you, I'd take the plant inside, but leave it outside als long as possible. Slight frost shouldn't harm it. Older plants might even survive outside, especially in larger containers. I've had the same plant outside for three years, originally because I had no space indoors & was too lazy to ...


2

I think this may be powdery mildew.. does it wipe clean? Please post a good closeup pic of the leaves. If so, before resorting to fungicides try cleaning and changing its environment. Clean each leaf by wiping them down gently ensuring a clean green surface. Make sure the plant is in a good sun spot. If the powder returns, try a teaspoon of bicarb in 1l of ...


2

Judging by the time the second photograph was taken the plant was drenched in water. Rosemary and Water at Gardenersworld.com links overwatering with yellowing of the tips. It also suggests "Rosemary doesn't need feeding of any sort, they prefer beneficial neglect, full sun and very well drained soil in summer, almost sand." Rosmarinus officinalis is a ...


2

Nothing, it'll be fine - it will, though, need as much sunlight and bright daylight as you can possibly give it, so a southfacing (or, second choice, east facing) windowsill would be perfect, provided there's no heat source directly beneath the window. If you can, move it into a terracotta pot with a good sized drainage hole, preferably using a sharp ...


2

Yeah I have this problem in Utah, it is just way too dry in the winter with the forced air heating... You can put the plants in a clear trash bag supported with a stick and make a micro greenhouse... This winter I have killed lots of things: Small olive tree, A couple of small umbrella acacias, A windmill palm, All of my citrus dropped leaves, A couple of ...


2

The Rosemary plant are of Mediterranean origin so biologically not able to cope with a winter. If you managed to get it in before the chill killed it, then the alternative is that you've over watered it. I suggest removing from the pot to inspect the roots to see if they're all mush or not. If not, it might have a chance of surviving but I doubt it. My ...


2

I agree those new plants don't look like rosemary. Could leave them for a little and see what happens or prune them out, but if you leave them don't wait too long or their roots may get tangled with the rosemary's. For your rosemary plant I had a similar situation and in my case it was primarily lack of light. Over-watering is also a common problem with ...


2

Yup, you've got aphids, spider mite...whatever. Is this the first time you've had problems? Go get some NEEM. A great sprayer...or a pump sprayer. Read the directions and cautions FIVE TIMES. Seriously, this is what they taught us in pesticide licensing!! Do NOT do this during the day. This stuff will help tremendously and like now. Make sure you ...


1

Unfortunately, keeping it indoors won't do it any good - Rosemary is a mediterranean herb, so it expects to be cold or very cool in winter, and have hot summers. It likes full sun exposure, regardless of the time of year, and does best in free draining, gritty soil. It does need watering, but watering well when its in a pot, with any excess allowed to drain ...


1

Rosemary is pretty resilient. I had one plant that had dried out from lack of care when I was away and it recovered after a few months. Just needed to water it. Pick the pot up and if it feels light, give it some water. Yours doesn't look dead.


1

Those do look like rosemary sprouts to me. The same thing has happened to my rosemary plant that I bought for a Holiday centerpiece. It wasn't getting enough light I suppose and turned brown. When I realized, I took it outside to live on the front porch where there is more light, in hopes it would recover. The main plant still looks brown, but today I ...


1

Most insects leave Rosemary well alone, they don't like it, but thrips or leafhoppers can be an issue. This is a link from the UK https://rosemaries.co.uk/TRSpests.html#R4 but it has a good image of a leafhopper, though if that's what the problem's been, yours may look a little different in the States; it also has some advice as to how to manage them ...


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