Hi All, can anyone educate me on growing Dahlias from seed. I grow Daylilies from seed and know the fun of seeing something unique that you created. ;)

I didn't save any seed, so I would need a source for Dahlia Seeds.

How long does it take to go from seed to bloom?

Do you get tubers from first year seedlings?

Love to see any seedlings you have created.

Still just dreaming about gardening here in Michigan, and will be for a while yet.

I bought some seed a few days ago, @TreeClimber - I picked them up on ebay, though you should be able to find them from more, um, reliable online stores. I am also pretty sure that I saw a Burpee seed pack at Lowes.

This isn't first hand knowledge - it is what I plan on doing based on reading.

I plan on planting the dahlia seed on a couple of 1020 flats with an inch between seeds. I will gently press the seeds into the soil and thing apply a light dusting of soil over the top of the entire 1020. Water it and keep it warm with 75 degrees being my target. Germination is supposed to be 7-12 days later.

The seedlings will be allowed to grow until they are touching one another - brushing shoulders. I will then transplant the seedings to individual 3.5" pots which I will rack in yet another 1020 flat (18 of the pots will fit per flat). They'll stay potted for the rest of the season unless they seem too cramped.

FWIW, I plan on making the soil in the pots a 50/50 mix of peat moss and potting soil. I am doing this to help manage moisture to a certain degree, but primarily because I intend to over-winter my roots in the planters. (Which may not work out - it is an do-nothing experiment.)

In the fall I will cut away surface vegetation and stack my flats up in the garage (which stays near 43 degrees through-out the winter). I *might* recover a few of the tubers and bag them up, but the plan is to break them out of the planters in spring 2021 and plant the roots / tubers. They will probably all still be mysteries as they are not likely to flower in 2020.

When you are planning, I think that you should decide pretty early on how many of the flats filled with 3.5" pots you want to wrangle. I am going to plan on 4 or 5 of them, dependent in part on how well or poorly the seedlings perform.

I also think that you probably need to temper your expectations. I hope to get about 70 plants to a flowering stage by 2021. I anticipate that less than 10 of these will be something that I will want to propagate to year 3 and then other annual cullings will happen. Keep an objective eye and work towards excellence.

EDIT: I failed to explain my reasoning for growing in pots. I don't care to scrabble for the roots as they will be fairly modest in size and probably easy to damage in such an immature state. Using the pot gives the seedlings the best chance to reach maturity.

When I first grew dahlias (~2005) I grew them all by seed. Here in Michigan, they must be started indoors and planted out after the last frost. They will bloom the first year.

Bedding dahlias are probably the easiest to grow and are available from many seed companies.

I found a wider selection of different dahlia type at Thomson & Morgan Seeds. Also, Swan Island Dahlias offers seed, but I have never tried them. I have purchased many tubers from Swan Island, just no seed.

If I remember correctly, I saved entire dahlia clumps to over winter them. Many of the clumps got fairly large and a single clump would barely fit in a standard paper grocery bag.

@frankrichards16 Thanks for sharing, Frank. I am way more excited about doing this if they'll flower in the first year

I planted 52 dahlia seeds on the 9th of March and today (just 4 days later), I've got a fair number of sprouts:



There are 3 sprouts in the photo should you enjoy seek and find games.

And yeah, I rolled all the paper pots by hand and filled them with peat moss (x1) and potting soil (x2) blend. I will probably add sand to the next blend for planting dahlias just to see if it improves my success rates. Anyone got a recommendation for a seedling mix?

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I've had several weeks to observe the dahlias as they grow. Typically they come up with two temporary leaves. These leaves are not permanent and will get replaced with real leaves as they grow.

Here is a seedling in super condition with both temporary / seedling leaves and the onset of real leaves:



The real leaves are in the center while the temporary ones are shaped like tear drops and V into the center stem. This plant is healthy looking and would not cause you much concern. Unfortunately, it is fairly uncommon for dahlia seedlings to be in such fine condition.

Dahlia seedling, as they put on permanent leaves, often look like this:



As you can see, one of the temporary leaves has dropped off of the edge of the paper container and the other is held at an awkward angle. The plant doesn't look well, but it is doing fine as long as the permanent leaves are doing well. And this is how the majority of my plants appear as they transition into permanent foliage.

Sometime the plants drop their temporary leaves almost too soon:



Here, very small permanent leaves are all that remain and the plant came fairly close to not making it. I've had a handful of plants that dropped the temporary leaves too soon and failed shortly afterwards. I am not sure why this happens.

It's been 3 going on 4 weeks now and I am nowhere near having a dahlia outgrow the little paper pot that they are in. I did have an occasion to transplant one and the root system seemed as though it had grown into a tight ball/clump compared to other plants.

I will be happy when I can get them in the ground! Two or three more weeks.

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I grew dahlias from seeds started indoors under lights (given by garden.org friends) and they did flower first year. I am in zone 7 but I think if you start seeds early it would work. Now would probably be late. Also the seed packets you see in stores are for shorter less showy varieties. I'm growing some of those in pots, not sure if they will set rivers, I guess I'll find out.

SCButtercup said: Also the seed packets you see in stores are for shorter less showy varieties.

I think they market those as 'border' dahlia.

I found a packet of 'cactus' dahlia on Amazon and an ebay seller that was culling seeds from large dahlia. My seedlings now have 4 permanent leafs with another pair on the way. Except for the weird one.

I have a plant that put on 3 starter leafs, and has gone triplets everytime it adds leaves. So it is working on 7-8-9 at the moment. I don't know what to make of that one.

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Top...any updates?

I got seeds off ebay. Almost 100% germ and about 20 plants grew. They are mostly singles and plain color. I got 1 striped red and yellow and 1 double in yellow. Lots and lots of true red and blue red. I am ordering bishops variety because I want the dark leaves. They were very easy and hardy in our soil.

I planted ~22 or so. I liked a pair of them well enough to plan on savings their roots and give them another year.

I probably won't grow from seed next year, but maybe every second or third year. I will try using my own seed.

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A neighbor used to grow well over an acre of dahlias (all marked and sectioned and all). We think, but can't remember if she bred the dahlias, but we think so. She would really watch some of them and talk to my mother a lot about them, before we could go pick the blackberries. I'm pretty sure breeding them wasn't that difficult.

As I do a little more research, I see that our neighbor must have been part of the Portland dahlia society and they have a long tradition of having people bring in home bred dahlias for friends to evaluate.

This year I am ordering dark leaf dahlias from seedman. (Great reviews) I am more interested in the foliage on shorter ones and $3 for a pkg is going to make it a fun try. (As I looked thru the tuber websites, I see I got a fairly special one that came from seed...whoo hoo!)

I like the random aspect of it. It's like getting little gifts as the flowers bloom for the first time.

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Here are 2 that I grew from seed. Most of them are like the first w/o the collar and a solid red or blue/red.

The second probably would have opened (or will open) but it's rather shady.

Most of mine were fire-engine red or dark red with yellow centers - almost all were singles (somewhat like a daisy). They also tended to be slow to flower and a lot taller than needed.

The pair that I am saving.... Yellow that blooms like mad and multi-petaled purple that blooms almost as freely as the yellow. We'll see how I feel about them after next year, assuming they survive overwintering and planting.

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Mine were mostly the red and blue-red, but they bloomed early. I even got 3 yellow, but they were late. I still have to decide if I am digging them. I had 3 deep, deep red-black that I didn't dig, I lost 2. The blue-red don't go with the garden may get to be experiments and stay in the ground.

The best thing has been watching all the bees getting more food for winter...most of my flowers and even weeds were gone by this time last year!

I liked the pair that I am saving. I don't think that they're very special appearance-wise, but they both are aggressive flower producers and bees were attracted in good numbers to both.

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The one in my bottom picture opened all the way and is very pretty. I'll try to move it to full sun next year and see how it does. (It's mostly in shade now.)

For anyone looking at this later: I just got seeds for next year: Diablo (black foliage) Red skin (Redish stems) and Bishop's children (dark foliage and short) from seedman. The site had good reviews. The packages were less than $3 and the shipping less than $6. (The site has lots of interesting flowers, so I got other seeds too) The dahlias should be all different colors, but short and fairly early from what I read. If it works like the seed I got from ebay, it was very easy germination on paper towel in sandwich bags and put into trays. It was about 6-8 weeks before it was warm enough to plant out and most if not all of them grew. I have heard that the short border dahlias have a tendency to not come back at least in my zone, so I'll either dig or let them die and try again next year from seed. I have also read that some dahlias don't make tubers very well, but I haven't dug up my "from seed" dahlias yet.