3,226 Garden Web Discussions | Dahlias

Hi rubies77, not sure if this will help? though worth mentioning. regards allan
Here is a link that might be useful: Dahlia Diseases

It must be fungus. You should treat them before storing.
Here is a link that might be useful: Dahlia Fungal Infections

Hi djc6535 your dahlia looks like it has leaf minor, which is a burrow into the leaf leaving trails inside the leaf like your plants show.
Systemic insecticide will often kill them though not sure what is available in your area? Here in Australia Rogor insecticide is often used to get leaf miner & as Wikipedia explains there are many lava which cause this problem.
Good luck
Here is a link that might be useful: Leaf miner


Dahlia heights are not precision. A plant that is put in the ground in mid June can quickly catch up to one planted in mid May. I planted one last July and it was blooming one month later, and I couldn't believe how fast it developed. I started one in the garage this year in March, and just NOW it's started to sprout (and I sincerely doubt it will do anything, but it's rare/old and I don't want to lose it.) I have never relied on a grower saying that a plant will be a certain size.

My experience tells me that 1) dahlias are very different in their growth habits 2) Height is unpredictable 3) Bloom times are very different. It all depends on the varieties you are growing. Generally speaking, larger blooms take a longer time to develop; and cactus varieties generally bloom quicker. But even that is not a science.
As far as plant height - I planted all mine within about 3 days; and now have some plants just peaking out of the ground; and others with buds!!
I'm dabbling in exhibiting dahlias this year and have tried to read everything under the sun about how to time out dahlias for shows. I haven't found any solid way to predict yet. The best advice that I have learned is to just grow a variety and take really good notes (planting dates, topping dates, first bud, first bloom, # of leaf pairs you left when you topped, # of leaf pairs from bottom of plant to bloom etc, etc,....) My wife makes fun of my excel spreadsheet dedicated to my dahlia plants. There is a payoff - If you grow the same varieties the next year you can plan when to plant, when to top etc. I'm following more of a plan this year according to some of the varieties I planted last year (i.e - if it took 57 days for a plant to bloom after I topped it; I know that I should top that variety about 57 days before the show)
That's probably more info than you needed unless you really want your dahlias to bloom at a certain time.

The purple giant turned bright white on the tips, magenta on the middle, and deep purple in the center. It looks fantastic and is doing wonderfully. Two of them have perked up. Ive noticed a difference in the structure of the... um.. bush? and foliage. The ones that look wilted tend to be less full and bushy. Much more lengthy, Also I felt the leaves, and they are perfectly healthy, firm. Not wilted at all. But their leaves look as though they are in a state of constant wilt. Because of out heat I try and keep them in shade. Dahlias do much better here when shaded for most of the day. They definitely aren't full sun plants down here. I try to plant them where there is full morning light and dappled shaded light during the afternoon. Some of them get hit by the after noon sun for an hour or so unfortunately. During the day it averages around 87. I say this because one day its 80 and the next its 90. We rarely reach 3 digits. and normally dont go above 95. I live nearish to the coast so it helps keep things cooler. At night I would have to say we reach from 60 - 70.

I live 1 mile from MIssion Bay, My dahlia's get direct sun from 3-sunset and they are throwing out lots of flowers and the leaves are healthy and it has TONS of them! i water about every 4-5 days and i use MG plant food slightly diluted strength, and i add a teaspoon of vinegar and a teaspoon of a witches brew i read about in another forum(take 1/2 cup garden lime, put it into a cottage cheese container and add vinegar, let it sit with out the lid as the reaction causes gas and foam. once the reaction settles take a teaspoon of the liquid off the top(it contains Calcium and MAgnisium) and my dahlias LOVE thsi mixture) good luck!
Eric


I have also had trouble with the ear wigs. When I purchased my home, there were some very large ear wigs here, the neighbors had large shade bushes that harbored them by the thousands. They have since subsided quite a bit, since i ripped all of the bushes out and destryed them. However, they still continue to eat my Dahlias and roses. I just went out there with the flash light, and sure enough, the ear wigs are out there. I sprayed all of my dahlias and roses with Garden safe brand, houseplant & Garden insect spray. I hope this works, I will report my results in a few days. I have not seen my dahlias bloom in three years because of the ear wigs eating them sooo bad....

If you usually leave your tubers in the ground then just go ahead and plant them. EVen if they do not bloom they will be storing up energy underground for next year. I Am doing that now with some late sprouters, including some I found in the bucket of blind tubers that was waiting to go into the compost and got lost....:-)

Why not try more?
Digging and dividing dahlias is hard work! If they do freeze, replacements can be easily bought. How much is your time worth?
Some hints: Be sure to mulch the plants with several inches of compost or dry leaves. Make sure they are not in a wet area as they will rot in cold, wet soil. Consider digging them in the Spring every few years and dividing the large clumps. As clumps get too large, they send up too many sprouts and the plants will become too crowded an be spindly. Be sure to control slugs and snails in the Spring as they will lay eggs on the clumps and the hatchlings will eat the sprouts before they come up. By the way, you can easily move clumps around in the Spring and they will do fine when re-planted.

I bought a plant of "Peaches and Cream" last year, and when I posted my fabulous "Peaches and Cream" bloom on another site, I was told and shown that it was more likely "Seattle" therefore, the big box store did mislabel. It does happen, but . . . all 5? I'm a fan of Duet, but wouldn't want an entire garden of it. I don't generally buy big box store dahlias, I buy my tubers one at a time from either dahlia club sales or from people that specialize in growing dahlias. But even dahlia growers and clubs make mistakes . . . it happens! When I helped package dahlias for my club this year, I learned just how easy it is to mislabel!

And I forgot the link:

Yes, that is a dahlia. I don't know the specific name of it but it is probably one of the bb size. This fall would be a good time to divide it. If it has been in place for many years you might need to just chop it in quarters with an ax and them remove all the damaged pieces. You will still have many tubers left to replant, or you can replant one of the quarters and share the others or plant them elsewhere. You might enjoy adding some other colored dahlias to complement it :-)

Are you sure it's a cutworm, because I am very fond of blaming everything wrong with a dahlia on slugs and this is no exception!
Not sure what kind of cutworms you have in your location, but this dealy below would be awfully tedious on 40 plants. And even worse in my phlox which they invade every year about now...
Here is a link that might be useful: cutworm device

I am raising dahlia plants in raised beds and they were doing so well. Now that they are getting buds they look like they are rotting at the surface. If I touch the plants they fall over. I did not stake the plants in the spring, which I should have, but this seems like either bugs or they are to wet. We have been getting lots of rain but the beds drain very well. I have about 25 plants and I am just sick about it. I have been staking the plants being very carful not to spear a tuber. Help!!!


Thank you for your comments Linda & Annabeth. My season has finished for now though will not be long before they start all over again ie September will start the new growth.
here are some other images;

Devon Calypso lovely formal red orange decorative mini;
Inland Dynasty very choice rich yellow cactus medium flower;

The next one is a mini decorative 'Hillier Fire & Ice';

The next one is a new one for me 'Kids Climax'

The next one changes color through out the season though is a terrific flower all the same, 'Breannon';

This last one is just a pretty decorative, "Bracken Sarah";

hope your flowers are out soon? cheers allan
Very beautiful! I just receive a bunch of dahlia tubers I ordered online. Well, I haven't planted them yet. I just hope that I could grow pretty dahlia flowers out from these tubers.