I grew dahlias from seed. Those plants have formed tubers/bulbs. How and when can I plant these?

As soon as your soil temps reach approx. 60 degrees.

@Calif_Sue
Let me clarify: Most of them haven't flowered yet. some never did flower but formed bulbs/tubers and started to die back. Bulbs you buy are brown and dryish, these are like potatoes


So obviously I should let the foliage die back first; then what? Do they need to 'rest before putting them back in the dirt? Should I leave them in the pot and do their own thing in their own time? Should I 'overwinter' them for a time in my basement?

Were these growing inside?
Everyone pulls their dahlia after the first frost in the fall and stores the tubers for the winter, we are all now getting our orders in for spring planting or potting them up to get a head start before planting them outside.
I don't personally know anything about the smaller pot grown ones, they will eventually forum the larger tubers.

Here is an article on dahlias that may be helpful.
https://garden.org/learn/artic...

I also moved your thread to the Dahlia forum, you can click on the blue link to the forum beneath the posts here.

Calif_Sue said:Were these growing inside?
Everyone pulls their dahlia after the first frost in the fall and stores the tubers for the winter, we are all now getting our orders in for spring planting or potting them up to get a head start before planting them outside.
I don't personally know anything about the smaller pot grown ones, they will eventually forum the larger tubers.

Here is an article on dahlias that may be helpful.
https://garden.org/learn/artic...

I also moved your thread to the Dahlia forum, you can click on the blue link to the forum beneath the posts here.

Yes ma'am, I had a pack of seeds that I grew under lights indoors. There were some that 'died' without blooming. I went to throw it out and found the tubers. Idk if I should leave them in the dirt or pull them and let them dry a bit? I don't know what to do with them

They need full sun to grow and bloom properly. At this point, it's probably best to leave them in the pot, set near a light source and if they are viable, they will soon sprout. Once it's warm enough, they should be planted outside, following the recommendations in the article.
Others may give you additional info, I know there are a few members that grow pot dahlias but they do put them outside.

BrookeV said:I grew dahlias from seed. Those plants have formed tubers/bulbs. How and when can I plant these?

When did you sow your seeds?. I did grow dahlias from seed and have one going on for many years outside. I didn't bother to lift them because in my winter that particular dahlia can stay in ground. In my case it is a single deep burgundy, fairly large sized dahlia. I need to lift most of my larger decorative or cactus dahlias. in about two weeks I expect my first killing frost. I let them stay a few weeks and then lift them; I store them first air dried inside and them pack them in wood shavings that has powder sulphur added in individual ordinary plastic bags with a few holes made. The purpose it to allow for some ventilation, but still keep the tuber moist and firm. Late winter I check if the tubers are not shrivelling and if needed I spray them with some plain water. They are stored in a cool cellar inside a cardboard box away from mice...Later in early spring I place the tubers over a moist substrate inside my greenhouse and start the sprouting induction. If I understand correctly, that would be where you would be standing just now. Once a shoot has formed, I pot them into individual bags and later in the season I harden them off outside. Finally when all danger of frost is over I plant them in ground. My larger varieties require all of this because my growing season ( dahlia wise) is too short and cool. If I don't do this some never reach blooming condition. Not all varieties have the same temperature requirements for them to bloom.
Arturo

hampartsum said:

When did you sow your seeds?. I did grow dahlias from seed and have one going on for many years outside. I didn't bother to lift them because in my winter that particular dahlia can stay in ground. In my case it is a single deep burgundy, fairly large sized dahlia. I need to lift most of my larger decorative or cactus dahlias. in about two weeks I expect my first killing frost. I let them stay a few weeks and then lift them; I store them first air dried inside and them pack them in wood shavings that has powder sulphur added in individual ordinary plastic bags with a few holes made. The purpose it to allow for some ventilation, but still keep the tuber moist and firm. Late winter I check if the tubers are not shrivelling and if needed I spray them with some plain water. They are stored in a cool cellar inside a cardboard box away from mice...Later in early spring I place the tubers over a moist substrate inside my greenhouse and start the sprouting induction. If I understand correctly, that would be where you would be standing just now. Once a shoot has formed, I pot them into individual bags and later in the season I harden them off outside. Finally when all danger of frost is over I plant them in ground. My larger varieties require all of this because my growing season ( dahlia wise) is too short and cool. If I don't do this some never reach blooming condition. Not all varieties have the same temperature requirements for them to bloom.
Arturo

Thank you for your response!

I planted the seeds in waves over the winter. I planted some in November and December and January.

The ones planted in November have either bloomed or are dying back. The others are just being green and idk what they are going to do.

So if I understand correctly; once the foliage has died back, I should dig them up and let them air dry. How long? When could I try to plant them again?

Or if I just kept them in the pot inside, would they sprout again this year or next?

OK BrookeV,
Your dates give me an idea of the timing. Tuber forming is a natural process in dahlias. Most dahlias start to store their energy inside tubers. Blooming is something independent from tuber forming. A few of the single (5 petaled) dahlias are grown as annuals. They may bloom and finally die without ever making tubers. I don't know the origin of your seeds. Your last picture shows a decorative type dahlia bloom. I would expect it to be forming a tuber. Once their bloom is over it will yellow its leaves. Then simply stop watering it. About two weeks later, cut off the stem about 3" above the soil lift the tuber and let it dry out with the top upside down in a dark warm dry place. Afterwards store it until you want it to sprout again as I explained above. If I understand correctly you want to grow them outside in your yard. When is your last predicted frost? then allow yourself about 6 weeks before and induce sprouting. Place it, cut-off stems upwards, on a tray with moist ( not wet) substrate in a very lit window. Spray it with plain water on an off and watch for the buds to swell at the neck of the tuber. Be careful how you handle it, because that is a very delicate part and you can easily loose the tuber and if it becomes bud-less severed from the bud. If so the tuber becomes useless. Once the bud/s have become shoots place it in a pot always in a very lit position. A couple of weeks later once the shoot has leafed out ( about 4 pairs of leaves) move it outside to harden off. This time away from direct sunlight ( it will scorch the leaves) for about 4/5 days. Gradually move it into full sunlight ( at first a few hours in the morning) and finally day long sun. By them you'll know where to plant and go ahead about it.

Because of your different seeding times you will have young seedlings that won't go dormant this season ( possibly those sown in December or January) . Treat them as if they had tubers underneath, as explained right above. These seedlings will need as much light as possible in a warm frost free position. A well sunlit window sill would be the best.

<Or if I just kept them in the pot inside, would they sprout again this year or next?
Because idk what you have sown, I can`t predict what they would do. In that case, I would empty the pot dry the tuber partly and restart as explained. A small tuber may grow and produce foliage but no blooms the first season, but yes the second. The leaves are going to pump that tuber with stored energy. Personally, I would not keep a dormant tuber in its former pot because it invites rot. Its much better to up-pot your tuber with new nutrient rich substrate each season.

Please let me know if you have any further questions.


Arturo

@hampartsum

I thank you very much! That helped and answered all of my questions!

BrookeV said:@hampartsum

I thank you very much! That helped and answered all of my questions!

You're welcome. I'm glad that I was able to share my experience.

Arturo