3,226 Garden Web Discussions | Dahlias
Looks like rust fungus. Neem oil should clean that up for you. If you're watering with a sprinkler, I'd stop that to keep it from spreading more... Can't stop the rain, though.
If you feel it's too late in the season to treat it, be sure to NoT compost the plants after frost, as the spores will hang out and have a party at your expense.
It is interesting what you all post for seedling pictures. We are dahlia breeders and are looking for nicely formed fully double dahlias with tight centers. Even though we only collect seeds from nicely formed dahlias, a large percentage of the seedlings do have open centers. Picture of an incurved cactus seedling in nice shade of lavender purple.
You're dahlias are absolute beautiful. I bought a flat of dahlias 2 years ago from a local greenhouse. I'm in Zone 5 so I have to dig them up every fall. So far this year the tubers I planted have almost doubled in size. I think I'm going to try to save some seeds to see if I come up with some different ones next year.
You could do that.... Just don't water until spring, protecting it from frost when it sprouts.
Problem is when you do that in consecutive years. Tubers tend to get bound up, black and nasty when undivided over time. Flowers can be lower quality, and many shoots from multiple tubers will compete for water and fertilizer.
Wait for the dahlia blossom to fade totally and let it dry on the bush. The stem should be dead behind the flower before you remove it. The seeds are in the base portion of the flower and you can clean off the dead flower portion.
Seeds look kind of like triangles, are black, and fairly hard. You can find tons of photos of the seeds online.
Now a warning: daughters of dahlia don't breed anywhere near true--the dahlia has 8 sets of each chromosome. Even self-pollinated flowers throw seeds that differ markedly from the parent, and the difference is only very rarely positive.
I am not much of an advocate of overwintering in the ground. Many people in mild climates do so but there are lots of stories of rodents eating the tubers. Good luck and too much nitrogen will cause overwintered dahlias to rot, especially if there is a wet winter. I assume the dahlias will go dormant in the winter and that you will not fertilize for about 6 weeks before they go dormant.
Hi beigestonehill, pdshop & Y'all;
Sorry to be so late with the answer to your questions.
Thank you for your thanks. Yes, some of them are "Yummy". They have to be to have entry into our family's and close friend's annual calendar
We are located on the North Shore of Ma, a few miles out of Boston. We fertilize with 5-10-5, 2 weeks apart early in the season. The 2nd one approx.1 week before planting. We follow the info suggested by Swan Island Dahlias after fertilizing, bone meal, no watering, slug bait etc.and add 5" X 5" X 2.5" vinyl squares around the sprouts when they appear to help retain water and act as a deterrent to slugs. Rabbits are very bothersome.
We do disagree with Swan Island's writings to not use bark mulch. We do on some of our beds to help control weeds.
Some years a few blooms appear early in this cooler climate while others are much later. The expected late bloomers are very questionable. We do have a late one that did blossom on 1 Sep.
Should anyone have other comments or questions please submit.
Charlie
Your method with adding conduit as the plants grow is really ideal! Your bed has a nice clean look to it that is enviable. Thank you for sharing, Charlie!
I just couldn't imagine finding the time to tie two hundred plants continuously, much less adding conduit to the ones needing it! Then you have to store all that pipe! One year I used pcv pipes to stake sixty plants, and had a lot of breakage as I couldn't keep up with it all with young kids and my two businesses. Kudos to you for doing this so well!
Although the horizontal row support and row twine is visible and may be seen as an eye-sore, it is the only way I will grow more then twenty plants from now on. It takes ten minutes to add another row of twine to a hundred plants at a time, and the tight hedge growing style keeps most weeds at bay. Disbudding, cutting and deadheading is the main maintenance with this system at this point, thank goodness. Then the real labor starts with frost, but let's not think of that yet. :-)
Check out how the same view as two weeks ago has changed...
Not directly bug related. Might be a fungus, invited by the overwatering, but not sure.
The foliage looks healthy, though sparse. Just pull off the brown leaves and black buds so the plant knows to grow out more, and discard waste away from your plants to avoid giving bad bugs or fungus places to hide/grow.
This occasionally happens, and it seems random with no clear cause. The plant will most likely shake it off, and start producing normally in a week or so.
A bit of fertilizer sprayed on the leaves might help it shake off whatever is ailing it. Think of it as a vitamin supplement to help you over a cold.
Well, I installed the watering system halfway through the growing season, so most of the early growth didn't get enough water. Now I have watered deeply twice a week and fertilized twice in August, and the top growth is much better. Now I know for next year! I'll have to see what I can do about the fungus potential, though. That's in a low spot along the foundation plantings. I will have to pull them up this winter and put in some new soil, or maybe just put the soil right over the top of them since I can overwinter in the ground.
for drgulley-friends in england say they think your flower is kilburn glow- to me the pics dont seem close but steve says he saw it at southport show and it is the same-kilburn won best of show a couple of years ago so probably worth growing anyway
Hi again;
I failed to mention in my previous posting we have found that spending a little more and using yarn rather than twine, we use green and buy it in 2 pound skeins, there does not appear any harm to the stalks/stems at all when tied loosely.
Charlie
Thank you for the responses. I use 52" tomato cages for staking. I have only minor problems with broken stems. Just the blossoms.
I prep the bed in spring with 10-10-10. Then feed once a month with 15-30-15. Next spring I will prep with bone meal to boost the phosphorus. Thanks for the idea. I'm not sure about boosting the Potassium. I put a few left-over bulbs on the edge of my corn patch. Corn is K-intensive. Although I get adequate blooms, the plants are two feet shorter than the same bulbs in my main garden.
Yes it is only certain cultivars: Wheels and Poodle Skirt. Both are novelty blooms.
It kind of depends on your local market prices--I'd take a look at what others charge there. Prices will certainly be far higher in more urban locations than in suburban or country ones.
'Round here, I can lay hands on a 4" potted plant for about $6-$7 for something unusual but not exotic. If I drove half an hour south I could do it for $4 to $5.
Are you sure either is accurate? All the pH meters I've had have read in the same range--all of them wrong by almost 1 point.
I did try a simple soil-water-reactant test out of idle curiosity. The pH actually was very accurate...if I were trying to test the pH of our water.
good Lord! I did start a hard topic. This year in CO, it has rained constantly. Never happened before. That will help wash out the salt in my soil as it was high in salt. I have basically solved the whole matter. Moving back to where I came from and had big, tall, thick dahlias. I do love some of the CO plants and hope to try some. Thanks for all your info.
My Harvey Koop is much more orange?
Just the dark red and golden yellow splotched on Harvey Koop. No orange on mine, though it looks like it from ten feet away. Could be a sport, or perhaps the time of year is effecting your blooms.