Dahlia - something is killing it
 

Hi,

I have one beautiful dahila in my little garden. She was blooming and growing wonderfully up untill 2-3 weeks ago when i noticed that the leaves and petals have what look like little black egg like things on them. They wash off easily but come back. They are killing my flower :sad: First it was the leaves (little dots/holes started appearing on the leaves but later whole leaves would be destroyed) and now its so bad that as soon as a flower opens up the petals get destroyed right away. I have no clue what it is or what to do with it. Any ideas?

BTW - I looked through the graden photos that you guys posted and your gardens are SOO gorgeous.

I would think some kind of spider. Or mite. Have you tried soapy water or just plain? Try soapy in a spray bottle. Wet the plant well. Rinse after with plain water just to get the soap film off. It may be too late to save.
A couple of options if it doesn't look like it's coming back. Cut it back to the ground, or close, and see if it starts putting out new leaves or............
you could take it up and store the tuber till next year if you want to try it again. No guarantees it will work but if you want to go to the trouble.

[url]http://www.dahlias.net/seabox/savem.htm[/url]

That sounds like you have little catapillars. They eat holes in the leaves and those black specks are their poop. They're common on zonal geraniums and usually treated with Diazanon or similar insecticide.

Sounds like aphids. I have those on my dahlia's every year. hate them. Talk to your garden store and you should be able to get a dust for them. Sorry I can't remember the name of the one I have (I believe it is called Rotenone and is a broad spectrum insecticide - but quite nature friendly as I have bee's). I dusted some on my aphids the other night and then just hosed them off two days later while watering the plants. But if you take a small sample in a plastic bag the garden store can tell you for sure what they are.

Thanks, I think i will first try to spray it with soapy water, if that doesnt work then i will move on to the insecticide.

Masha - could you take a picture of them? Maybe it would make it easier to identify.
Does TO have a pesticide ban yet? So many places do now.

Yup, we have a pesticide ban. I will take photo tomorrow, i just finished watering and it washed all the little black dots off (i want the photo to have it all on it...). I never actually see any bugs or anything on it.... I did spray it yesterday with a general instecticide spray, but will keep an eye on it and if dots are back tomorrow, will take photo and do soapy water..

Ok, I wondered. The one pesticide mentioned is banned in Canada. The other is still available. However, it causes Parkinson's disease if injected into rats. Not sure I would be using it either. I use just the soapy water in my greenhouses. Just my :2cents:

okay, well the dots are there... so here are a few photos, hope this will help determine who the culprit is (see the block particles on the petals). I also incuded a photo of what they did to the some of the leafs. As you can see, when the flower opens, they eat the petals so only the inside petals are left, anyways, i will let the photos to the explaining:

Masha - I am not entirely sure what is going on. You can try adding a couple of cloves of mashed garlic to that soapy water too. That may help a little more.
There are so many bugs and so many new ones coming around it is really hard to say. I have been reading about flea beetles that can do this damage. I also read about earwigs. I didn't have that problem when I planted dahlias but maybe I was lucky.

A few tricks for getting rid of or at least partway eliminating earwigs. They like dark places to hide during the day. They tend to do their eating at night and they leave behind black feces. Take a piece of garden hose and lay it near the base of the plant(s). Early in the morning you can just pick up the hose and shake it into a container with soapy water or you can squish them. Another idea is to take a plastic bottle - pop or water bottle - cut off the top, put a small amount of tuna fishy cat food (or even tuna fish but the experts say the cat food works better) in the bottom of the bottle. Put the part you cut off back on but put it on upside down. Tape it onto the bottle so it stays put. The earwigs go in after the food and can't get back out. Then you can do the same thing, drown in soapy water or squish them.

I don't know if it's too late for your plant. You may just have to wait till fall and lift the tuber after the first frost. If it looks good you can store it over winter and plant it again next spring. Good luck. :fingerscr

Masha,I love Dahlias,but I have never had any luck with them,they always get bug-eaten and nothing I tried ever works,so I stopped planting Dahlias.
There seems to e a lot of bugs out there this year:yell:

Hmm doesn't look like aphids by the pics. I'd bag one and take it to a garden centre and ask them what it is.