Little black things in top photo are aphids. White flecks of top of leaves are shed exoskeletons.

Damn. That's a bummer. They only seem to be on my mums. Are aphids host specific?

Some are, many are not. But they are among the easiest of common plant pests to control. Squish off gently with your fingers or hose them down with a strong stream of water.

I just looked at all my other plants that was near my mums and none looked like they had it. I did squish some but some were in the inner leaves I could not get to unless I rip off the leaves itself so I sprayed all of them with horticultural oil. Does horticultural oil kill them? I know it works for mites and scales.

Yes, it will kill them. But I would consider that overkill in this situation. I would have just hosed down the plant well and called it good. Too many beneficials and other critters feed on aphids and that is not enough of an infestation to justify anything beyond your hands or water. And pending frosts or cold weather will kill them off anyway, although eggs may overwinter.

in my MI ..... mums are cut back hard for winter ...

what do you do with them in warmer zones???

suppose neither of you have had frost yet .... do aphids winter over actively??? ... do you really need to treat for them this late in the year????

ken

Yes.. well I actually soaked my mums real heavy with the spray. The picture doesn't show too much but the infestation is pretty bad. Its on all 10 of my mums. And I wanted to kill them before they make eggs. I had aphids on my sedum too which came back from last year so you can tell they successfully overwintered. Also I need to kill it now before it might spread on my other plants! I cut them back in late winter so the rootball isn't bare and exposed all winter but cutting it back in March maybe too late and the aphids may have may already be on their way for the season as opposed to cutting it back in late fall right when the mums go dormant but that would mean its going to be bare all winter-long. Ken your area experienced frost already?? Tonight it is supposed to go down 40 degrees for us which is a little concerning

Often plants under stress are more likely to attract insects. I would get those planted in the ground and I think they'll be much happier.

My garden doesn't do too bad and I rarely if ever go out of my way to spray for anything. It almost always works itself out and the garden is usually stronger for having done so, or has taught you something along the way.

All the beneficial predators here are useless. There are about 3 roaming cats that regularly pass my garden and I don't see any difference in chipmunk population. There are many spiders and some ladybugs around and yet you still see mites and aphids. I went straight to chemicals because I've lost patience on dealing with mites last year. Squished them everyday and washed off every single leaf of my citrus 2 times a week but they still persisted. So I'm assuming all of these pests are very resilient. But good to know aphids are not.

Katob, they are newly divided plants in propagation pots so not meant to be planted in the ground.

Newly divided plants could go directly in the ground in your zone. No propagation pots necessary.

You grow your plants in whatever way you'd like, just an observation on stressed plants. Also another observation is there will always be a few pests around, without them the ladybugs etc would starve... as far as lazy neighborhood cats go, cn't help with that one.

Citrus is an awful pest magnet for all kinds of things, and mites are one of those pests which often develop resistance to one or more groups of pesticides. Because commercially grown plants are usually sprayed much more, they often carry these mites with them.

Laceyvail, I have my reasons for growing these in pots.

Of the 2 years I've been gardening I learned that without resorting to forceful elimination methods, getting rid of pests is pretty much impossible. But I never really dealt with aphids yet so I'll see.

My mums usually get heavy infestation of aphids in spring. If I wait a week or so, the ladybugs arrive (ta-da!) and clear up the aphid problem 1-2-3.

Sometimes they'll come back and when I do the Chelsea Chop in June, the aphids are discarded along with the prunings.

I seldom see them this late in season but wouldn't worry too much about a few now. Frost'll get them.

Heruga, please take this comment for what it is from a caring and long time gardener. I am worried that you will suck all the joy out of your gardening experience. I have watched your posts about rot, excessive heat, overwintering...

I agree with GG that squishing bugs and a heavy stream of water is generally all you need. If you resort to chemicals you will be wiping out the beneficial bugs too.

I am so delighted when a young gardener comes on board. As an older gardener I would strongly encourage you to simply enjoy the ebb and flow that is gardening. Yes it can be frustrating at times but the joy that it brings far outweighs the bumps in the road. Many of us have gardened for years and our gardens have survived with few losses and little intervention. I say this with affection.

peren.all has stated it very well. 2 years is just a mere drop in the bucket in a gardening career :-) Take it from gardeners with many, many years of experience (almost 50 for me) in all sorts of conditions that when we advise and suggest you ignore some issues completely or practice moderation in others that we are speaking from many years of accumulated knowledge and practice.

I am simply speaking from my own experience with the pests I've dealt with. I don't think 2 years or 50 years matters for this. I have eyes just like all of you do. What I observed is what I observed. Unless you guys are calling me a liar. I don't think pests start behaving differently once you become an experienced gardener. Do I really need 50 years of gardening experience to say that pests were not eliminated by hosing it off and squishing them? Especially when I have done that for my 2 citrus 3 times a week LEAF by LEAF on the whole plant all summer, fall, and winter 2017 long? Nope mites did not go away. Aphid eggs also overwintered on my sedums from last year after a very harsh winter and they came back this year. This is what I am observing, contrary to what you guys are saying. So unless you guys are calling me a liar then theres no reason to immediately dismiss and discredit my observations and experiences just because I am a newbie.

Heruga, please do not take offense!! And we are not calling you a liar. What we are trying to convey to you is a need to step back a bit and not to panic or overreact.

Plant pests are a fact of gardening life. You will never eliminate them all..........nor should you necessarily, as that will upset the natural balance. But they can be managed and often they are best managed by doing very little. Or as little as you can get away with.

Sometimes it is just a matter of providing the best growing conditions. Aphids are often attracted to plants that develop a lot of lush new growth from overly rich soils or unnecessary fertilization. Sometimes just growing the plants under leaner or somewhat harsher conditions will significantly reduce the risk of infestation. I will say that in all my many years of gardening, I have never seen aphids actually kill a plant, even very heavy infestations. Spraying down the plants routinely or cutting off the most affected parts (generally the newest growth) does help a lot and will keep populations at manageable levels. And encouraging beneficials or other wildlife to the garden will also make a big difference.........IME, birds are nature's most efficient "insecticide" and the more birds you can attract to the garden, the less pest issues you will you have to deal with.

The point we are trying to make is that all gardeners deal with the various issues you have encountered and yet their gardens survive and even thrive. Drought, heavy or persistent rainfall, cold winters, very hot or dry summers, insect problems......we have ALL encountered them and our gardens have lived to tell the tale. What more years of experience gardening will provide is the knowledge of what is a serious problem that needs intervention (or plant replacement or substitution) and what you can safely ignore or treat as innocuously as possible. And the vast majority of us tend to steer away from heavy pesticide usage as we have learned that it upsets the natural order and very often can cause more problems than it solves.

And added years of experience will often influence what sort of gardening choices you make. Some plants are just a lot harder to keep happy or are more prone to problems (like indoor citrus) so you need to weigh whether or not the plant justifies the effort.

But please take the advice provided by very experienced gardeners not as a criticism but with the good intentions with which it is given. Yes, 50 years of gardening does bring one knowledge, experience and wisdom that just a couple of years doing so does not provide. It is obvious from your posts that you still have much to learn - we are just trying to help you get there :-) And even very experienced gardeners learn something new on almost a daily basis!!

No offense was intended and I completely agree and echo GG's comments. Age matters not but experience does. You will evolve as a gardener as we all have. If I do not learn something new everyday I consider it wasted time. We glean knowledge by being open to others experiences and accepting or rejecting what works for us. We are only trying to help you in your gardening journey.

After trying to keep numerous pests off my rhodendrons which had curled, bug eaten leaves (I saw mites, various flies and tiny caterpillars, slugs, etc) by spraying with strong stream of water I thought of trying this:

Each morning I have an inch or two of coffee in the pot which I dilute and pour over the rhodendrons on a rotational basis. At first I worried it would ‘burn’ or otherwise harm the leaves but after two seasons of doing this, the leaves are dark and glossy. I guess these insects don’t like coffee!

give it a try on one plant, coffee is acidic but diluted it just might work for you on your lovely chrysanthemums (or try tea).

Before running out and dousing your plants with coffee (or tea) you may want to read this. Would not be my first choice :-)

Wow, quite a discussion on used coffee grounds, thanks for linking. I really enjoy Linda Chalker-Scott, thanks again.

I have put used coffee grounds around strawberries and lupines... which didn’t seem to stunt their growth but also didn’t deter slugs, which is what I tested for that one summer. I’m back to composting the ucg.

Is your concern due to the diluted liquid coffee being acidic? Or caffeine in the soil? I’m trying to extrapolate your thinking based on the interesting ucg discussion.