I don't know what active ingredient you applied, but normal insecticides work quickly on contacting aphids and don't have a residual action on aphids. I would not spray again. But then, I never spray aphids unless, if they are super-thick, with soapy water. They are nearly harmless and always go away after a while.

Like Michael said, nearly all insecticides are contact sprays including soap. That's why they are fairly useless to use as a preventative. If the bugs aren't there when you spray it won't kill them when they come. There are a handful of systemics but they're expensive, toxic and usually specific for certain insects. So spraying insecticide for insect A for insect B is a waste. Anything that got hit yesterday when you sprayed will die anyway, rain or no. I'd wait and see if the problem goes away now before spraying again. Besides, like Michael said (He's a really smart guy so always listen to him.), aphids are really pretty harmless and can be taken care of with a hard spray from the hose. If it rained hard it may have taken care of the buggers for you!

Well, I am not intending on sounding rude or offensive, but it reads like none of you read the topic. :(
I said that I bought the insecticide (Rose Clear UltraGun) not made it, and there already were aphids and I killed them the previous day using the spray, however, it rained when I was asleep (At night) and cleaned off all the spray.

I was asking if I should spray again when I am not expecting any rain, or don't spray it till the required time?(4 weeks later, which will be lots of aphid and Japanese beetle damage.)
I used to see aphids disintegrate bushes in a matter or weeks during my childhood and I do not want the same to happen to my bushes. :(

thanks for replying thou!

I have never seen that product and don't use insecticides regularly. Our Aphids are small, maybe you have a different kind in your location.

Since the replies did not cover your concerns about the use of that particular product, I would email the company and ask. Seems to me you would probably be okay to wait til Monday to hear from them.

Hope that helps

I don't mean to sound rude or offensive, but the answer is still the same. Most of the forumers here do not spray aphids with anything more than a strong stream of water from the hose or, in a few cases, with soapy water. Why? Because insecticide for aphids is definitely overkill. They will do almost no damage, and shortly, the good bugs (like ladybugs) will come along and gobble up the aphids. Of course, if you are spraying insecticides, you may have no lady bugs left since the insecticide may have killed them off. In the meantime, just be gross and run your fingers/thumb lightly over the aphid-covered bud--that will kill them off best.

But if you insist on using insecticides when they are not needed, then by all means--FOLLOW THE DIRECTIONS.

As to Japanese Beetles, that's a whole different ballgame. Either post separately on the topic or use the search function at the bottom of the page to call up the 100s of earlier threads on Japanese Beetles. The simple truth is, nothing except extreme drought (at the right time of the year) seems to make a big dent in their population numbers.

Good luck. : )

Kate

I looked up the product. It is a UK product, combination systemic fungicide and insecticide. If the product was able to thoroughly dry on the leaves before rain, then it is in effect. I would not reapply, especially since that would mean a double dose of the systemic fungicide. Wait, and apply as per the interval provided on the label.

I think diane_nj has the most rational response ... and most responses around here are not rational when it comes to insecticides.

Aphids can do considerable damage, if what you are wanting are good blooms. Isn't that the whole reason to grow roses? So if someone says they don't do much damage to the bush, that may be true - but what the hell good is the bush if the blooms are shot?

JMHO, but most of the insecticides recommended for roses are systemic in nature - meaning the rose bush absorbs the spray and provides extended killing power to the insects that try to eat parts of the bush. So as diane says, if the spray had a chance to dry, most likely it was absorbed by the bush and rain won't affect it. However, the interval of effectiveness for the chemical is still key. The half-life is not forever with most insecticides these days.

I also disagree about the JB's. Imidacloprid (Merit or some Bayer products) will kill them dead. However, imidicloprid lasts about 2-3 days. It's up to you whether you want to stand out amongst your rose bushes and spray the buds and blooms every 2-3 days, but it can be done. They may take a bite of some of them, but they'll be dead when they do. Everything has a price, though. Do this and most likely you'll end up with spider-mites in August. I hate it, but I've come around to just treating JB's with physical means, instead (chopping them in half with your Felco's works pretty good). They will disappear by August.

I'm not as prejudiced about insecticides as most folks around here, but they're correct when they say spraying a lot of insecticide will promote spider-mites.

Conserve (spinosad) is a good "green" insecticide that will do a number on aphids but hurts other insects (good ones) very little. It also does a good job on thrips, but total control is out of the question. Still, you can spray it almost every week with a little alternation with something else every 3-4 weeks and have no worry about killing everything in sight. ;-)

Roseclear Ultra has a neonic in it called acetamiprid - it is a systemic insecticide. You DON'T want to be using it like a contact sprayer, ie, nipping out every 5 minutes sprayng aphids. As long as it had say, 12 hours before rain, you are fine. For me though, you should switch to separates, a fungicide and an insecticide. The insecticide has a recommended 4 week interval with max 3 doses per year, the fungicide every 10-14 days if necessary so using rose clear ultra is not ideal. One other thing, night time not the beat time to spray - we get heavy dew which washes the spray off. Japanese beetles a none issue in the UK so don't worry about them. Don't spray when blooms are open(ing) - it's toxic to bees.

Leave the bugs alone. The almighty had a plan and the little bugs get ate by the bigger bugs. I have a poison free yard and like it

please lets not let this descend into a big argument about chemicals.

So if someone says they don't do much damage to the bush, that may be true - but what the hell good is the bush if the blooms are shot?

If you read more carefully, you would notice that I listed THREE ways to get rid of aphids without having to resort to insecticides. I did NOT say, just leave the aphids alone.

Compared to JBs or RRD or a severe case of blackspot, no, aphids don't do much damage--mainly because the lady bugs and other predators come along in a week or two and start gobbling down the aphids. But I said that above also.

Kate

In 37 years of growing, the worst damage I have ever seen by aphids on roses is that, on some stems not all, a few of the upper leaves are mottled and wavy, and the flower is smaller than normal by say 25%. And this damage will not occur if you practice minimal control, such as spraying water or soap on the stems that are really encrusted. So those who go in for competitive exhibiting will definitely want to control aphids in the run-up to a show. But I don't worry about minor temporary cosmetic damage.

oooh---exhibitors! Now I get what's going on.

Most of us do not exhibit. We grow beautiful roses with beautiful blooms in our gardens and that is where we enjoy them--IN OUR GARDENS. (Well, some people also like to take a bouquet into the house to enjoy.) Most of us are not growing roses competitively, nor do we garden with all attention directed at the exhibit table. Fine for those who enjoy doing that, but the rest of us don't. We are trying to beautify our gardens and yards.

Different purposes for growing roses probably result in different gardening techniques. For those who garden in order to have lovely rose gardens in their yard, aphids are no big deal -- if you follow one of the three non-insecticidal methods I covered above. And my blooms do not come out shrunken or distorted. They look normal, big, and healthy.

Kate

When we sprayed regularly (because we were exhibiting, and because we were told it was vital to do so) we had plenty of aphids to chase around. We ALSO had to spray for spider mites.

Now, we don't spray.
I haven't seen an aphid in 3 years. Seriously. The only bad thing about that is that I no longer get annual visits from flocks of bush tits who come in and eat up all the aphids. Very rarely see spider mites, either. Bees and lizards play here.

If I saw aphids in one isolated spot, I would brush them off.

Aphids just aren't a biggie deal. Not worth bringing out the "big guns," and Neonicotinoids really are BIG BIG guns.

Jeri

Sorry -- Double posted. Again.

Which allows me to recommend again a gardenhose for aphid control.

Jeri

This post was edited by jerijen on Mon, Jun 24, 13 at 14:22

I've never seen aphids do any meaningful damage, they are more of a cosmetic issue, sawfly larvae, a different story. Aphids do seem to coat my celsiana though, in huge amounts too, so I spray that with systemic spray to keep them at bay.

I'm sorry that you felt I missed the question but in rereading your first post I still think that both Michael and I answered your question. If the aphids are no longer present there is no need to respray. It's done it's job already. Spraying when the bug is not present is a waste of time because they work on contact. If there's no bug there's no contact. Residual spray on the plant will not take care of any bug infestation that shows up down the road. If you see more bugs later then spray again.

As for the fungicide part of that spray, read the label and follow the directions on how often to use it. But I would try to find a product that is strictly a fungicide and not a combination. That insecticide part will only be killing off the predator insects, that are needed to keep your roses healthy, when the bad bugs aren't present and you use it.

I am admittedly a novice rose gardener. Last year I used Bayer 3 in 1 to "help" my roses because that's what someone with lots of experience growing roses told me to do. The roses I had were still chewed to bits.

Then I read a valuable piece of advice-- which was to give nature a chance to work things out.

So this year, I did. I have tree frog tadpoles and damselfly nymphs in my small garden pond. I have grown frogs, lizards, dragon and damselflies everywhere I look. And very few aphids. Very few chewed up leaves and distorted flowers from whatever other critters like to feast on roses in this part of the country--far fewer than last year using Bayer 3 in 1!

My biggest problems are Japanese Beetles, rabbits, and deer, which I don't think I can do a whole lot about except discourage their presence.

If I used chemicals, I suspect the balance would be "off" again. And I like the good bugs not just for what they do for roses, but for the mosquitoes they love to eat! We have far fewer mosquitoes this year than previous years, and maybe it's in my head, but I think it's because we have an abundance of damsel and dragonflies and frogs.

So for whatever it's worth, I wouldn't spray chemicals for aphids before a rain or after-- unless it's with a garden hose.

I use IPM with my roses, Integrated Pest Management I walk my garden ever day and keep a close look at what is going on in the garden. But it also means looking for other means to handle the problem. If you have any questions about something like that ,ask your local Extension Office or a local Consulting Rosarian.
Years ago I did the same thing. I don't use insecticides at all and I exhibit.
I teach Pesticide Safety and I don't recommend he use of insecticides unless you have to. I haven't seen very many have to situations in my garden except the time where I was swarmed with jb's. There is a right way and a wong way to fight them.

Seil, no, it's a systemic insecticide, not a contact one. Obviously it does kill on contact but that's not its intended use.

With respect for all -- I think what we're dealing with, here, is the effect of years of propaganda to the effect of "Better Living Through Chemistry." (I bet Disneyland no long has that exhibit.)

We have at last learned that Chemistry is NOT the only good path to better living (or even better roses) and that, sometimes, less really is more.

Jeri

Except chemicals like H2O, they're good right?

H2O....yikes that is not something we have much of here! :)

Dutch, that's what I did..I didn't use anything the last 2-3 years to kill bugs..and this year my roses are spectacular and bugs are at a mimimum. It's amazing.

This month, we will probably have our first $200. water bill of 2013. This is despite the fact that our once-lush lawn is only a memory. And despite the fact that we are steadily-reducing the amount of water the garden needs.

If you live in Southern California, soon or late, you learn just how precious a thing water really is.

Jeri

It's hard to imagine. I am not even metered!!

Well, you don't live in a land where drought has always been a major or minor note -- and where a large % of your water is obtained from somewhere else.

Most of our water comes from one specific acquifer -- and that acquifer is diminished in both quantity and quality through over-use.

Jeri

I don't understand why they haven't cracked desalination yet.

Desal is expensive (and not the best quality of water from what I hear)

Our last water bill squeaked in at $100 and we are hoping to keep it about there. Of course we spent a bunch of money setting up a system to water as much as possible with as little as possible of water.

Kippy -- is that monthly? Or bi-Monthly???

Jeri

Eventually, we will have to rig a system to send laundry water into the garden.

You know, they are actually putting a desal plant in for one of the local acquifers that flows through this area. Because it is coming through ancient seabed, that water is so saline as to be barely potable.

Jeri

That is monthly Jeri, is yours bi-monthly?

That includes a large vegetable garden and orchard.

Ours is bi-monthly -- so we're not so different.

Jeri

If you don't want bugs on your rose plants then spray. I prefer the systemics, because they will kill for 3-4 weeks as long as it doesn't get washed off in the first few hours after applying. I also think it's a good idea to alternate between different chemicals - don't give the bugs any more chance of developing resistance than you need to.

I've seen aphids cause plenty of damage - including causing the death of a rose bush by so severely weakening the plant that it perished.

I simply cannot visualize an aphid infestation severe enough to kill an otherwise healthy plant.

Nor do I think anyone was suggesting that the Original Poster simply ignore an infestation of aphids.

The point that was made was that, with pesticide already sprayed, and no aphids present, further use of pesticide is not needed.

And that, if in the future, the only problem IS aphids, they could easily be eradicated through less-catastrophic means.

Jeri

Wooooooow, so I left this post for a while and look at what it turned to, LOL
OK, so, let me clarify a bit, I sprayed again.
But this is because the day I sprayed the plants on, was
very wet and the plants were dripping.
The mistake I did here was spraying dripping wet plants.
Shortly after, like 20 minutes, it rained again and this time the rain was heavier that the previous time so I think the insecticide was all cleaned off and yes, it was all gone because the days after the continuous rain, Aphids attacked.Again.
But after spraying the plants, there have been little as to no aphids anymore. :)
I also took another measure to reduce aphids; I removed all weeds around.
Another thing is that right besides the house next door to mine, there is this neglected tree, not grown by the government or public.
It is one of those trees with winged seeds (Not like literally, "winged") which is, as I said, neglected and collects all diseases and pests known to plants.
I wish I was exaggerating, but on that tree, each and every leaf has more than 500 aphids feeding on it and this is a big tree we're talking about.
I cut off all branches reaching into my home and thus, the aphid problem has decreased.
The reason that tree is not gone is because (It grows on the edge of a wall) if they cut the tree off, it will fall right on my neighbour's home. haha
I just want my roses to be healthy and happy, and not looking as bad as every other rose in the neighborhood which are all, Aphid infested catastrophes.

Thanks for all the replies!