3,226 Garden Web Discussions | Dahlias
I've heard a couple folks that have success storing in the fridge, but heard many more sob stories about how the tubers rotted trying that method.
I'd keep them in the original packing material at room temp, and pre-start them 4-6 weeks before planting time in small pots with just-damp potting mix so they will be nice and ready to go into the ground.
I start my dahlia seeds now and start tubers in trays next week. Both bloom around the 12 week mark for me give or take cici is correct, tubers produce (usually) the larger named varieties.... Seeds and small plants that thrive in containers! I love both!
Thanks for the responses. I am planning on raising the beds as best i can with 3" leaf gro. We are 25 miles west of Baltimore and DO have clay but not extremely heavy. The garden I am using for the dahlias has been in veg production for more than 40 years. It is LOADED with worms. My chickens had a feast when i was digging the tubers! The dahlias did great last year! I also do not want to till these beds annually. My biggest thorn will be the weeds. I covered the entire 30x60 bed with commercial weed cloth last year. Worked great but i know the weed seeds last forever!!! There are going to be 15 16'x3' beds with 4' paths that i will put cloth on again. But haven't decided how to deal w weeds in the beds besides hand weeding... Grass clippings? I don't have time to waste....thanks for any ideas!
A speaker at the last club meeting suggested four layers of newspaper under any type of mulch to keep weeds at bay through the growing season. The newspaper and mulch break down and add to the soil composition when you dig the tubers.
He added that color inks in newsprint are all made with vegetable dyes and not of heavy metals like they used to be, so color newspapers are safe to use in the garden.
Edited to add...
The speaker was a director of a University Agricultural Extension Office.
Six on one, half dozen on the other. An earlier start might help them bloom earlier...if they're getting enough sunlight to develop. That's about four hours of direct sun per day absolute minimum (six would be far better).
Really, a well-planted dahlia should blossom about six to eight weeks post-planting, and I've gotten that down to four by feeding well and making sure they have a LOT of sunlight (eight to ten hours). It does depend somewhat on the dahlia as well. Most of my cultivars seem to be fast.
Both Seattle and Procyon are in the 3-4' range, depending on feeding levels, sun amounts (full sun will give fuller dahlia), water amounts, and so on. Excellent care can cause both to exceed their normal maximum heights and flower more, of course.
Dahlia absolutely require about six hours of direct sun per day, so make sure your indoor location features that. I raise mine outside in my south to west garden where mine receive nine to twelve hours of sun. The mailbox garden dahlia gets sun from sunrise to sunset.
Post-planting, it usually takes about 2 months for the first bloom, but it varies a lot by the individual tuber. I've gotten flowers from my dahlia (Blue Boy and Sun Lady) in as little as five weeks. On the up side, dahlia are in full swing in late summer and early fall when the rest of the garden is getting a little tired.
Number of blooms varies widely by care regimen, plus the larger-blooming dahlia tend have fewer blossoms per plant at any one time. The Seattle, with 8" blooms, is likely to have fewer blooms at once than the smaller-blooming Procyon at 4". Anything from four to fifteen blooms at once is well within the normal range.
There are exceptions. My Color Spectacle can outdo the Blue Boy, featuring fifteen six-inch blooms at a time while the Blue Boy has eight four-inch blooms.
But again, sunlight levels are directly related to blooming strength. If your indoor locale is short on sunlight, the dahlia will bloom poorly, if at all.
The 'official' designation for a giant dahlia bloom in the US is 'AA,' over ten inches. But just because that is the POTENTIAL of the bloom does NOT guarantee that size from your plants. Throwing a tuber in the ground and walking away will produce disappointing results if you are going for larger then six inches. Good cultivation practices like watering sufficiently, fertilizing, supporting the branches and disbudding are essential to get huge blooms.
Again, I would treat them differently depending on if they are divided in individual tubers or stored as whole clumps.
I'm not a big fan of drowning them for an hour, though some growers do that. Either they already have enough moisture retained in the tubers to keep the meristem tissue responsible for new growth alive, or it's shriveled past life. Soaking might deteriate its last defenses, leaving it open to fungal and mold attacks.
If you have whole or half clumps, I would put one in a pot and lightly moisten the soil, leaving it at room temperature. The soil would moisten it while protecting from spores.
If you have individual tubers (like chicken legs), I would take a couple and put each in a sealed ziplock bag with a squeezed out moist cotton ball. You can monitor it closely for sprouts or roots, and get a good idea if the rest are worth saving.
Either method, done now with only one or two, will give you a good idea if you should be seeking new dahlia tubers from another source for this coming season.
Hope this different perspective helps.
Cheers!
I'm sorry to hear that there are no cultivars with higher resistance to powdery mildew. With some plants (roses, phlox) there are such varieties. I will admire them in other peoples' gardens.
As for water or not with powdery mildew, watering foliage to wash spores off is the best policy. PM is different from other fungal diseases in this regard. Best to do it in the early morning so that the foliage can dry and not invite those other diseases.
See, I've heard the opposite argument that spraying the foliage might allow the splashing up of spores from the soil... Or perhaps that was nematodes...
Sorry to hear that PM is a deal-breaker for you with dahlias. Thorns are the deal breaker for me with roses, so I suppose we all have our reasons for what we grow, whether or not it really makes sense. ;-) for instance, I'm okay with raspberries, but roses are not happening! (At least for 2015... I reserve the right to change my mind in 2016.)
Usually a spritz with a water sprayer (like people use when ironing to damp the clothes a touch) is more than sufficient.
Mine wrinkle a bit every year (I just checked, they're wrinkled a bit) and make it through fine--but most of my varieties are tough as nails to begin with.
I've always dug mine in the Autumn, but in 2013 neglected to dig my sister's ( downtown Hamilton, Ontario - 6b, in a sheltered spot). Even though last Winter was VERY cold and harsh, her dahlias came up beautifully. I've deliberately left hers again... Worst case scenario - plant some of my extras if hers don't come up.
Hi, I saved a whole bunch of seed from a garden nearby, a lady grows a ton of nice named variety dahlias in gardens and big pots all around this restaurant, last fall I got to collect all the seed heads and I have a plastic grocery bag half full of seed heads. Most of what I saw from her plants they were average size, not huge dinner plate types, 4-6" flower heads. Last year I grew a bunch of the seeds and am growing even more this year, its fun growing seeds not knowing what they will look like, its like christmas morning when a bloom is about to open! They were roughly 2-3' tall with 4-5" blooms. If you'd like to see the flowers I ended up with I just shared them here:
https://allthingsplants.com/thread/view/26205/2014-Dahlias-are-in-bloom/?offset=60
my acct name is jaym1818 and you'll see my post on page 4 and a row of pictures
Thanks Cici !
How tall will the plants (from tubers) be at week 6 ? Week 8 ?
Honestly, I've always jumped the gun on timing and have 12-18 inch plants to set out, so I couldn't tell you exactly even if there were exact heights to share with you... Depends on if tuber was sprouted when you preplant it, and on variety. Some, like Pooh, will spring into action and be over a foot tall before you know it. Others seem to take forever to wake up and get height.
If you don't have adequate light, they will be more leggy between the leaf sets, hence taller.
Most experienced growers I've talked to prefer the plants to be around 8-10 inches high. This avoids the stalks from being 'flimsy' from the pampered inside, but enough height to avoid the worst of the slug nibbling. I typically plant my tall ones a bit deeper, taking any leaves off that would be underground. Tubers will form at those leaf junctions by the fall.