What is deadheading and why should you deadhead dahlias?
Taking care of dahlias involves the usual necessities of feeding, watering and mulching.
But another question you may ask yourself is do you deadhead dahlias as well?
The answer to that question is am emphatic yes! To get prolonged and repeat flowing, you definitely need to deadhead your dahlias.
Deadheading dahlias is a critical part of dahlia care. It means removing the remains of the spent flower head once the petals (or ray florets) have dropped off. We dead head dahlias, and other flowering plants, to prevent seeds developing. By doing this, the plant’s ‘desire’ to set seed is frustrated, so it puts its energies into growing more flowers. Continual deadheading means the dahlia plant will flower until the onset of winter.
- What is deadheading and why should you deadhead dahlias?
- How to deadhead dahlias
- When do dahlias bloom?
- What to do with dahlias after flowering?
- Should you deadhead dahlias?
- The two step trick for deadheading dahlias
- Best tool for the job – bar none
- Frequently Asked Questions
- What you might need to deadhead your dahlias.
- More on taking care of dahlias
How to deadhead dahlias
When do dahlias bloom?
Dahlias bloom from mid summer into autumn, even flowering on until the first frosts if you deadhead them as described in this article.
If you live in a warm climate with lots of sun, your dahlias will bloom earlier in the summer than they do in cooler regions. If you are growing dahlias somewhere sub-tropical, like Florida, you’ll may find that your dahlias go dormant in the heat of summer, flowering instead in fall, and again in Spring.
Individual dahlia flowers last for four or five days and maybe up to a week in some varieties. Interestingly, many dahlia flowers change as they develop from bud to a mature bloom – some change shape and many change shade, often from deeper to lighter colours.
What to do with dahlias after flowering?
Once you know how to grow dahlias, they can flower for extended periods but only if you, the gardener, help them do so.
After reading the paragraphs above, you’ll probably realise that you have a simple choice about what to do with dahlias after flowering.
You can allow nature to take its course and let the dead flower head go on to develop seeds. When the seeds are ripe you can collect them and sow them in Spring.
However, be aware that dahlias do not come true from seed. This means that the dahlia that grows from a seed will not identical to the parent plants. This is how dahlia growers are able to develop so many new and unique dahlia varieties.
Should you deadhead dahlias?
The alternative to letting your flowers go to seed is to deadhead your dahlias. In fact, if you want your dahlias to flower as much and for as long as possible, you have to deadhead the spent blooms.
So yes, if you want more dahlia blooms, you should deadhead your dahlias.
The two step trick for deadheading dahlias
As we’ve seen, deadheading – removing spent flower heads – prompts the plant to produce more flowers. This is because removing the spent flowers deprives the plant of the potential seeds that evolution is driving it to produce.
But, it can be a little bit harder to deadhead dahlias, whatever variety of dahlia you have, than it is to deadhead most flowers, unless you are aware of one important fact – how to identify the spent dahlia flower head.
How to deadhead dahlias step 1 – Identify the spent flower
This is what makes deadheading dahlias a little bit tricky.
The problem is that once all the petals have fallen from a spent dahlia, the hard sepal at the base of the flower close over and what is left looks very much like like a bud.
So unless you know how to tell the difference between the buds and the remains of the spent flowers, you can end up removing the very buds that you are trying to induce into flower.
Fortunately, it is pretty easy to tell which is which when you know how. So here’s the trick:
How to tell dahlia buds from spent flowers
The buds are rounded and the spent flowers are cone shaped
Dahlia flower Buds
Take a look at the picture below.
These are buds.
The bud is rounded, a kind of flattened sphere of compressed petals, with the calyx (the hard green/red outer ring of sepals) fanned out below the bud.
Of course, the many dahlia varieties produce buds come in all sorts of different shapes and sizes. So, here is another selection of dahlia buds, just to make sure you can recognise a bud when you see one.
Dahlia dead heads – spent dahlia flowers
In contrast, what you see below is the spent flower.
Notice how the overall shape is pointed rather than flattened, a cone instead of a sphere. In addition the outer sepals of the flower have folded up to enclose and protect the reproductive parts of the plant.
These are what you need to remove.
And here is a selection of the dead heads to give you an idea of the way that they can look in the different dahlia flower varieties.
How to deadhead dahlias step 2 – Cut right back
This is the easy part.
When you remove the dahlia’s dead head, don’t just cut it off below the flower. If you do, you’ll leave a flowerless stem that will just look ugly.
Instead, cut back, with sharp secateurs, to just above the point where the flower stem joins a main stem.
As you do so, you’ll probably notice a couple of tiny buds nestling there. With the removal of the spent flowers, those will sparked into life and they will bloom in a week or two.
If you are attentive in taking care of your dahlias and keep up your deadheading regime all summer, you’ll have blooms until the plant is knocked over by the first frost.
Take a look at the video above to see the 2 steps for deadheading dahlias in action.
Best tool for the job – bar none
These are what I use to deadhead my dahlias - and for all my pruning. I've tried many different brands and nothing beats these Felco No 2 pruners in my view.
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- Lifetime guarantee, all parts replaceable
Frequently Asked Questions
How to deadhead dahlias in pots?
The short answer is that you deadhead dahlias in pots in exactly the same way as outlined above for deadheading dahlias in your garden beds.
If you want the detailed answer on deadheading dahlias in pots, follow these steps:
- Ensure you have a sharp pair of pruning shears or secateurs.
- Identify the spent blooms, as indicated above. These are cone shaped.
- Grasp the stem of the spent flower just below the flower head, and trace it down to the next set of leaves or junction.
- Make a clean, cut just above this point. This removes the old bloom and takes away the stem that is not only ugly but could introduce rot to the plant.
- Discard the spent flowers to maintain cleanliness and avoid potential pest or disease problems.
- Deadhead you potted dahlias regularly during the flowering season to help encourage more blooms
- While you’re deadheading, check the moistness of the soil. Dahlias use a lot of water and dry out frequently in pots. So, it is beneficial to keep the potting soil consistently moist and feed the dahlias with a balanced liquid fertiliser every few weeks during their growing season.
How long do dahlias bloom for: do dahlias bloom all summer?
To my mind, one of the greatest strengths of dahlias, is the fact that they can go on flowering from mid-summer right until the first frosts. Depending on where you live, that could mean that you can have dahlias in bloom for three, four or even five months.
So, yes, dahlias can bloom for much of the summer, and much of the autumn as well. However, the most important word in that first sentence was can. We, as gardeners, have to help by deadheading dahlias, as outlined in this article.
How to prune dahlias – is pruning the same as deadheading?
Deadheading is a form of pruning. But is is pruning that we carry out specifically to stop the dahlia form setting seed so that it will produce more flowers.
There are also two other kinds of dahlia pruning that is carried out for specific reasons.
Firstly there is ‘pinching’ or ‘stopping’ dahlias. This is done early in the season when the stems have two or three sets of leaves. This encourages the plant to bush out and produce more stems, and therefore, ultimately more flowers. Read more on pinching dahlias here.
The other specialist type of pruning is called disbudding. This involves removing all the flowing stems and buds from a main stem except one. This then encourages the single remaining bud to produce a particularly large flower. This is a technique used by exhibition dahlia growers.
How to keep dahlias blooming – is it just about deadheading?
Deadheading is the way that you encourage the dahlia plant to form more buds, and thus more blooms. But to keep dahlias blooming, you also need to make sure that the dahlia has sufficient sunlight, is well-waterered but not sitting in waterlogged soil and has the right amount of nutrients.
When your dahlia plant begins to set buds, it is therefore a good idea to switch from feeding it with a balanced fertiliser to one that is higher in potassium. This is because potassium encourages the production of flowers and, in the right plants, fruit. Tomato feed is higher in potassium and can be used to encourage your dahlias to keep blooming too.
What you might need to deadhead your dahlias.
If you’re just deadheading your dahlias, you can just as easily use kitchen scissors. But if you’re anything like me, then you’ll be scanning the garden for anything that needs a prune or a bit of cutting back while you’re there.
I pretty much never step into the garden without my Felco Classic number 2 secateurs. These are the best secateurs or pruners I’ve ever found – and, believe me, I’ve tried plenty.
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More on taking care of dahlias
Read more on how to grow dahlias, with full cultivation notes here.
Dahlias for cut flowers: 20 Inspirational dahlia flower arrangements
10 of the best orange dahlias for the hot borders in your garden
Small spaces, big impact: Master the art of growing dahlias in pots
Discover 10 of the best red dahlias for your garden
Discover how deep to plant dahlia tubers – your guide to all conditions
How to stop or pinch dahlias for bushier plants and more flowers
Dahlia spacing: how far apart to plant dahlia tubers
Dahlia gall: identify and prevent leafy gall and crown gall in dahlias
When to plant dahlia tubers: solving the dahlia grower’s dilemma
Heat tolerant dahlias: beat the heat with these 120 choice varieties
Martin Cole has been an avid plant lover and gardener for more than 20 years and loves to talk and write about gardening. In 2006 he was a finalist in the BBC Gardener of the Year competition. He is a member of the National dahlia Society.
He previously lived in London and Sydney, Australia, where he took a diploma course in Horticultural studies and is now based in North Berwick in Scotland. He founded GardeningStepbyStep.com in 2012. The website is aimed at everybody who loves plants or has been bitten by the gardening bug and wants to know more.
Gardening Step by Step has been cited by Thompson and Morgan, the UK’s largest mail order plant retailer, as a website that publishes expert gardening content.
Thanks. Glad to get that info on dead heading dahlias. Looking forward to more blooms.
Do they come up every year? Can’t remember the term names.
Oh! Are they annuals or perrenials?
Hi Jill. They are perrennials. Although in very cold areas you may need to lift and store the tubers over winter.
Question; do Dahlia’s grow & bloom best in clay pots? Plastic? I have gophers and don’t trust them in the ground,….
Thanks for getting back to me /us 🙂
Lesley
Santa Cruz, CA
Hi Lesley
On the whole they do better in the ground and are easier to look after (not so much watering). But there’s no reason why they can’t grown in pots. I’ve always grown dahlias in the ground but I’m actually growing a dahlia in a pot for the first time at the moment, so I’ll keep you posted on how it goes.
You can use clay or plastic pots, although I’d usually choose a clay pot because sometimes plastic pots can get really hot and damage the roots of the plants. This is less of an issue if it’s a large plastic pot.
When growing dahlias in pots, you need to make sure they don’t dry out and keep them well fed – seethis post on growing dahlias.
Hope this helps.
I have had great luck storing my dahlias in Pro-Mix. It is light, fluffy and dry. After lifting, cleaning and drying, I divide each clump, which is the hard part, then put each division in a ziploc bag , covered with Pro-Mix then zipped shut. These are then placed in the coolest corner of the basement. Nearly 100% success every year.
Sounds like you’ve got it very well under control Chuck.
I agree dividing dahlia tubers is a bit hard. I always end up with a few loose ones with mo growing point. That’s why I always wait till there’s a sizable clump.
Thanks for your tip.
Your dahlias are abutoslely amazing. Are they perennials where you live? We have to lift the bulbs in the fall, which is why I’ve never tried to grow any.
How do you prepare the plants for winter? They are brown and look dead. Do you cut the plant off at the ground?
Thanks,
Hi Neil
Yes. Cut them back at ground level. If you’re in a frost prone area, lift and store them over winter. Otherwise mulch them and wait for spring. Details are here …
I liver in central Florida, will the blooms continue all year or will plant die back in the cooler weather?
Hi Lynn
I think they’ll still go through the perennial plant cycle of growth and die back, but you’ll probably get a longer flower season. You could try some heat tolerant varieties, e.g. Bloodstone,Thomas Edison, Juanita, Prince Noir, Jersey’s Beauty, Bishop of Llandaff, Deuil du Roi Albert, Surprise, Lavengro, Princess de Suede or Winsome. Also make sure they are well watered but that the soil is free draining. They won’t cope with being waterlogged.
if I leave the tubers in the ground over winter do I need to cut them to ground level first
Hi Harry
Yes, once they’ve been hit by the first frosts or bad autumn weather, you should cut them down to ground level and then apply a good layer of mulch. They should be fine if your temperatures don’t get much below -5 on a regular basis, although the tubers could rot if you get lots of rain and the soil is sodden for extended periods.
Thank you so much for this info! I wasn’t sure how to deadhead my dahlias – at the base of the flower or the stem, but you certainly cleared that up for me! I am in NYC and have mine in pots and window boxes, so it is easy for me to see the spent blooms. And no, you’re not the only one that thinks of the #GratefulDead when using the term “deadheading!” You have a new fan in me! LOL!
Hi Kristin Thanks for your comment. I’m glad the info has helped you. I’d love to see your display of Dahlias. I think I’ll have to try to work out a way for readers to upload pics of their gardens and plants.
I’ve now included a page where readers can upload their own garden and plant pics, tips and gardening stories. Click here and follow the instructions.
Hi guys,
I’m growing dahlias in a large plastic pot for the first time. Until two weeks ago, i had beautiful red flowers with bright yellow centers, and multiple flourishing buds. However, they suddenly started to die out and the new ones are now small pink-yellow flowers and few buds. The soil hasn’t gotten too dry (I used micracle grow potting mix). The weather in the north east has been ok – some night are still chilly but not below freezing, certain days humid but not too bad. I’ve frequently moved them inside and outisde the house to protect them from heavy rain.
What could be potential causes? Is there a recommended water regiment i should be following? What about light exposure? What else could I do that might help me get them back to big red beautiful dahlias? Will they come back?
Thanks a bunch!
Hi Gabriela. Sounds like a tricky problem. One cause could be that the soil is too wet. Dahlias can’t stand being waterlogged, so I’d suggest you make sure that there is good drainage through your pot. Plastic pots can hold water much more than clay pots, so I’d check that the soil is not waterlogged around the roots of the plant, even if the surface seems dry.
Another thing that dahlias need is a good supply of sunlight, so I’d try to keep them outside, in full sun , as much as possible.
If they’re in miracle-gro potting mix, it doesn’t sound like they need feeding. Sometimes over-feeding will kill plants, so unless they’ve been in the mix for a long time, so that all the nutrients in the mix have been depleted , I’d hold off on the feed.
Hope this helps. Let us know how it goes.
Gabriela,
Just saw your post about your dahlias looking sad and noticed that you used Miracle Grow,. I discovered a website that grows dahlias in the northwest area, I believe Oregon and on their site they really explain everything you need to know about growing dahlias. I believe that Miracle Grow has too much nitrogen. There are certain fertilizers for dahlias that you need to use. Check out their site it is very informative. Hope you see this since your post was back in 2014.
Good Luck
I just got my first dahlia and it is a deep blood red type but as they age they begin to turn a lovely pink . They are the same flower ,it just changes color ! Some of them are bi- colored now . I wonder if it’s the type of dahlia ?
Do you let the blossoms completely die , before deadheading. Or do you cut them off, when they start to turn brown. Thanks. This is my first year , I am growing them in containers. Thank you. For all of the information.
Hi Sheila
It’s up to you really. I do it when I notice a bloom is fading. I think that technically, as soon as the spent flower is removed, then the immature blooms get a signal in the form of a hormone to begin the flowering process. But, if you’ve got a plant with plenty of blooms, then some are likely to get to the cone-shaped, spent flower stage before you catch them. The best advice is just to make sure you deadhead on a regular basis so that you’ve always got some new blooms coming through.
I am growing dalias in South Carolina for the 1st time. They are in plastic pots in almost full sun. However, the petals are turning brown before the bloom has fully opened. What do you think the problem is?
Hi Gayle
Like all things in gardening, Dahlias like it just right. They need sun and they need to not be waterlogged, as I’ve said above. But – if the sun is very intense, especially at midday, the petals and buds can burn. Also, when the weather is warm, make sure they get enough water – not so that the roots are drowning for any prolonged period, but enough to ensure the soil doesn’t dry out for any length of time. This can be a problem with any plants in pots. Also check out your feeding regime. I’ve read, though I haven’t verified this yet, that they should not have fertilisers high in phosphorous. So make sure the middle number in the NPK number on the fertiliser packet is not too high.
Also are there any problems with the leaves? Are they yellowing for example? Is there yellowing around the veins? These kids of symptoms can signifiy nutrient deficiencies or imbalances.
This is my first year growing Dahlias, and I am having a problem with something eating the flowers, little bits at a time!!!!! What can I spray on these gorgeous flowers to protect them??? Also, I find that earwigs like to tuck in the flowers as soon as they start to fade…….that’s easy enough to handle, as I deadhead very quickly, but I would like to ask…”Do Dahlias attract earwigs or do I just have an overabundance of earwigs, and not enough good hidey spots for them?????
Hi Shirley
Earwigs are known to be attracted to dahlias, so there is a good chance it’s the earwigs that are nibbling your flowers. I’m reluctant to recommend spraying because then you’ll also kill the good bugs like ladybirds (ladybugs) and hoverfly larvae that will protect your plants from other pests like aphids.
One old gardeners’ trick to deal with earwigs involves placing a small upturned flowerpot stuffed with straw or tissue paper on stakes in amongst your plants. This provides the kind of daytime hiding place that earwigs like. You can empty out the pot each afternoon and destroy the earwigs that collect there, or just empty the contents into a plastic bag, tie up the end and put it in your bin. This should help keep the earwig population under control.
It’s hard to recommend a product if you do want to use an insecticide as what is available will depend on where you live. For example, in Europe now very many insecticides have been banned. In any case, you might find it is best to use a granular product rather than a spray as this can be more targeted.
Hope this helps.
This is not another question…….I just forgot to click the “Sign up to our newsletter” box!!!!!
how often should i water and feed my dahiias? this is my fist time gardening and im loving it…
Hi Barbara
I’m glad you’re loving your gardening experience. There are some dahlia growing tips here. Keep the soil reasonably moist, but not waterlogged. Feed them with a nitrogen-rich fertiliser in early summer and a potassium-rich fertiliser once they are flowering. Once a month should probably be enough.
i have started to dig up my plants and have noticed after a week they seem to be getting soft. I have them laying on paper bag in basement. I have planted these for 3 or 4 years and did not realize they were able to be saved. I would just notice that they were soft and mushy and I would throw them away. Someone told me peri all and I thought they were annuals. I am so excited because I have picked well over 300 flowers this year off of my dahlias. I sure hope I can save them from year to year. Thank you for your help…I really enjoy the tips on your site.
Sandy
Hi Sandy
Glad you’re enjoying the site.
Make sure you lay the tubers upside down to dry out. They have hollow stems and water may well be lying in the bottom of the the stems that you cut back.
This water needs to be drained out or it can make the tubers rot.
My dahlias do not have seeds in them, when I dead head them. I wonder why, can anyone tell me. I’ve had them for years, and they are lovely’
Cheers
Adele Anderson
Is it normal for my dahlias to brown almost every day?! I seem to find myself deadheading spent flowers everyday! I’m new at everything flowers so help please!
Hi Johanna
Individual blooms should last a few days. But if you keep deadheading, you’ll get more blooms, so ultimately there’s more deadheading too.
I recently bought some plants at a garage sale. one of which she said was Dahlias. at the time, nothing was growing, BTW ~ i live in So. California ~ it’s in one of those plastic long (abt. 2ft long and 6in deep) containers. It’s growing, but the earwigs are eating the leaves. Thanks to your hints above, I will set up some “earwig traps”, So I wanted to put these in my garden. Do my dahlias like morning or afternoon sun? And do you have any tips on the transplanting? I was just going to cut away the planter and set the whole thing in a large enough hole…
thanks, Pat
If you’ve got enough room and can dig a big enough hole, that sounds like a great way pf transplanting, Pat. They’ll generally prefer morning sun, as afternoon sun can be especially fierce. But they originate in Mexico, so you climate should be fine.
Why do the petals of my dahlias look dead? Too much water? Thanks
Hi Brian
It’s hard to say. It could be too much water, or too little, or too much fertiliser or too little, or scorching from hot sun. Sorry that’s not much help but there are so many variables in gardening. The best recovery regime would be to cut back all the dead or dying stems. Make sure the plant is reasonable well watered, then mulch with an organic compost.
More info here
Hello Martin, i want to say thank you for all your insight, knowledge, and time you give to answering peoples ? keep up the great work.
No problem Paul. Thanks for your kind feedback
I dreaded headed my plants about 6 inches under the bloom and now the stem is brown where I cut (but green everywhere else). I also was using standard kitchen scissors (new gardener here, just ordered shears!) I tried cutting back a few more inches the first time I noticed they were brown, and it just happened again. What can I do to get them to start growing again?
Hi Joan
You need to cut back to just above a leaf bud, below the flower. The part of the stem you cut back inevitably goes brown, so if you cut it back to the nearest bud, you minimise the stem die back
Do you trim back the leaves and leave stems on dahlias? I’m in northern MN, have them in pots, and the greenery is growing like crazy. Actually over taking other plants in pots with em. If I can trim them back, how do I know which to trim if flowers heads haven’t started yet? Thanks so much!
Hi Denise
Look out for tiny buds between the leaf axils. Otherwise, don’t worry too much. If they’re flourishing, they’ll produce new flowers – just a bit later than they would have if you hadn’t come them back.
Look out for tiny buds in the leaf axils (where they join the stems). Otherwise, don’t worry too much, if the plants are flourishing they’ll flower, just a bit later than they would have done if you hadn’t cut them back
I’m not a new gardener, just new to container gardening! I have a gorgeous purple dahlia in a metal pot (might change to a ceramic pot soon), and with the heat and sun here on the southern coast of Spain, I’ve noticed a few dried, browning leaves. Too much water? Too much sun? The pot isn’t huge, but could it be warming the soil too much? It was root bound when I bought it, and this metal bucket was the only thing big enough I had to use. Plus it looks pretty cool in this bucket!
Any suggestions? Thank you in advance!
Hi Vicki
Yes, those metal pots do look cool but they do cause the soil to overheat and they’re not usually that good at draining. I’d definitely try a different container.
Thx….my Dahlias look fabulous! I’m may enter them next year at the fair. My neighbors and friends can’t believe and neither can I. Lol
In my garden, I have 5 clumps of dahlias. Suddenly, all 5 have started to die. Two started first and then the rest followed suit. I am so disappointed. We have had really hot weather and are on strict watering which is all by hand either by hose or watering can. I feel like I have been pretty good about watering, but it could be a factor. Nothing else has died. I could probably dig up one plant, but I would not have any idea of what I would be looking for. Reading the above suggestions, I could cut the plants. I would really appreciate any help you can give me thank you.
Hi Jane
It probably would be a good idea to dig up, or carefully down and around, the tubers in one clump to see what’s going on. It sounds like the tubers may have rotted, but that seems unlikely if you are on water restrictions – unless there is poor drainage around them. Otherwise, it could be some bug at the roots – Cutworm or such like. Also check for earwigs in the leaves and flowers.
If they’re not totally dead, and there are no obvious signs of tuber damage when you dig, all I can suggest is cut them back, feed, water and mulch and hope for the best.
Martin, this is my first year growing dahlias. When they first started to bloom, they were a very vivid red color. Now they are starting to fade on the sides and turn an orangish color. Is there something I can do to make the color of the bloom look more vivid again?
Hi Paige
You could try a fertilizer which is higher in phosporous than other nutrients. Phosphorous promotes flower growth, but I’m not sure whether it will improve the colour of your dahlias. It could just be a characteristic of the variety you’re growing.
hi
I am first time, first season growing a variety of dinner plate dahlias.
I just did a round of dead heading in my garden.
I live in Los Angeles, CA for reference, and my plants are starting to go a bit brown and sad looking.
We have had a good couple weeks of heat and dry weather.
I am trying to bump up my watering.
Should i add some Sluggo to my plants? I can’t tell if they are sick or just need more water.
thank you!
Sounds like it could be the heat Sandra. Keep up regular watering. Mulch with an organic mulch. Maybe use a seaweed foliar feed.
So I’m growing dahlias in a big clay pot in southern California. They are in full sun and well fed and watered. They bloomed beautifully for about a month. Then it kind of just stopped. I’ve cleared all the dead leaves around the stem to let it breath and have removed dead head close to the base as you mentioned. The remaining stems are roughly 2 ft tall and falling over now and not producing any more buds. Should I cut the plant down?
Sounds like if there are no bus, you may need to cut right back Matthew. But have a good look in the leaf axils. Sometimes there are some tiny buds hiding there. If there’s any life left in them, you can stake the stems.
Hi there ! It’s my first year planing dahlias in pots in zone 6b. I’m nervous my dahlia one of it is browning and the others are blooming? The leaves and stems are browning and I’m finding myself cutting the brown leaves and stems off every month.is that normal? Thank u!
Hi Victoria
Maybe the browning plant is suffering underground. See the reply to jane Griffiths above.
Apologies for not keeping up with comments. Been working on another project: The Self Determined Life. Nothing to do with gardening, but you might like it, so take a look and sign up for the newsletter.
Thanks
Hi Martin,
We live in Toronto. This is our first attempt at growing dahlias and had amazing results this summer. however in a rush to clean up the yard for winter I pulled out some tubers to store them away for winter. It looks like I did that a bit too early. Will my tubers not have eyes for next year? My question to you is, do I have to wait till the first frost to pull out the tubers for storage?
Hi Aishafik, sorry for the delay in replying. I’ve been tied up with some other projects. They should be ok. Follow the advice here
Hi I wonder if anyone could tell me how to keep my tubers over winter I have just lifted them and very wet and soiled up I live in the midlands uk
And it is very wet here?
Hi Cliff, sorry for the delay in replying. It’s probably too late now, but follow the advice here
Hey my dhalias are growing pretty fine in the bed. But the ones in the pot have got leaves turning black and the leaves are dry to touch. We have had quite windy nights past week. Please help
Still waiting for some help regarding my dhalias
Hi Erum
It could be the wind, especially if it was hot and dry. Dahlias have quite soft leaves and they’re prone to wind burn. Prune off the damaged leaves and give them a good water and mulch. Feed them too if it’s been a while since you did.
Hi ya I’m moving house and its only March and would like to take my Dahlias with me, they are planted in the garden and blooming hard. Can I cut them back to just above the bulbs and dig them up, then leave them to dry out for replanting next season ??
Hi Tracy
I see you’re in New Zealand. Yes that would probably work. Leave it as late as possible. The problem is they may be a bit weaker next year because they won’t have had a full growing season for the energy from photosynthesis etc to be stored in the tubers. So you’ll need to give them a good start with feeding, mulching, compost next year.
The alternative is that you could dig them up and let them finish the season in pots.
Oh ok I didn’t think to do that….
Very helpful thank you for your time. :^)
Thank you!!! I “rescued” eighteen 1.25 qt Starsisters this morning for $1 each. Just after I started giving them TLC and deadheading them, I started questioning if I butchering the beauties instead! So glad to find your site and the helpful distinction between spent and unspent, and also to find I’m not the only one who couldn’t tell the difference. 🙂
Thank you!
Lisa in 7b
I bought some beautiful Dahlias for the first time at Costco. I planted them, forgot the snail bait, and when I checked on them the next day, something had made quite a feast of them. I have since put down some Deadline to deter the pest, but they are not snapping out of it. Been a few weeks. They look a little droopy and, well, very eaten. How do I perk them back up? I’m in Northern California, and it’s nice, but not hot yet. I’m not sure why they are looking like they don’t like their little sunny spot. Any suggestions?
Hi Joy, maybe something is still eating them. Check for earwigs. They like a meal of dahlias. There are some details about dealing with earwigs here: https://gardeningstepbystep.com/how-to-grow-dahlias/
i have saved my dahlia tubers for several years, but this year when I started them in the house, something has gone wrong with. the stems of the leaves. They are curved downward and the leaves are curling in from the sides. the leave is also curved down. i have gone out and bought some hybrid dahlias. They are beautiful, but I am wondering if these can be saved and grown again the next year. I went to every garden centre looking for tubers, and everyone was sold out of 18 in to 24 in. I grow these in pots so I don’t want really tall ones. All that was left was these potted hybrids.
Hi Adrienne. You can try them but they may not be strong enough to regrow next year. Check how big the tubers are at the end of the season. if they look pretty solid, it might work
I want to know if hybrid dahlias can be taken in and kept until the next summer. Do they have a tuber the same as regular dahlias
Hi Martin,
It’s nice to know I’m not crazy for thinking plastic pots were killing my plants and then transplanting them all. So I’m having trouble with a dahlia that I planted in a pot. It’s my first time with them and I completely misjudged how large they grew. I need to transplant it into a much larger pot I have, but I’m worried about the whole plant dying for the year.
If it has outgrown the current plot then it won’t thrive anyway Harley. Just do it carefully and it should work.
Just had a hail storm, what to do? My guess is to cut back the stems like dead heading?
Hi Marilyn. Yes – just cut back damaged stems to a bud. They should regrow.
First off thank you for all the information!!
I absolutely love dahlias, I discovered them last year at a farmer’s market so I’m still new.
I dahlias used to have perfect blooms but not buds are only partially opening and when they do the flower is deformed (pedals are asymmetrical, some short others normal). In addition to that I now have white lines on my leaves (probably leaf miners). Are the two problems from the same pest? I’m not sure what I’m dealing with. The deformation isn’t genetic since originally the flowers.
Any idea what’s causing this?
Thank you,
Nathalie
Hi Nathalie. Sounds like leaf miners on the leaves. Could be earwigs munching into the buds before they’re fully formed. Have a good close look at the plant to see if you can see any critters.
Hi there,
One of my plants recently got attacked by aphids! I read somewhere to spray them with soapy water and then spray with the hose to remove them the next day, but it looks like I was too late. If I cut stems right down, is there any chance they will come back?
Thanks?
Hi Michelle, Yes, if you cut them down they should come back. Dahlias flower late anyway, so depending on where you live and how early the first frost is you could still get flowers this season. Maybe you just need to cut back the damaged sections, not right down to the ground.
I planted my dahlias in mid-May and to date have not seen any growth. I dug one up and found it to be still firm and just beginning to create roots. What am I doing wrong?
Jo
If it’s getting roots, you probably just need to be patient Jo. As long as they are well fed and watered, just give them some more time.
I z
I am planting dahlias in plastic pots for the first time. Can I leave the plants in pots and bring inside during the cold Canadian winter? Can I then divide and repot plants in spring. The plants have buds and blooms now.
Hi Kaye
Normally it’s best to take out the tubers and store them dry – details are here: https://gardeningstepbystep.com/how-to-grow-dahlias/ .
You could try leaving them in the pots but they might rot, unless kept very dry.
Martin, are you typically always following this page or do others answer questions as well?
Hi Emily
I do monitor the page but can’t always keep up with the comments. I’m more than happy for others to answer and add their wisdom.
Last year my dahlias were a brilliant pink. this year the same plants are very pale in color. Do I need to add something to the soil? (denver, colorado)
Hi Rob
Sometimes this happens when the plant is stressed. Check whether they’re getting enough water, feed with a ferilizer with a higher phosphorous level (as this promotes flower health) and mulch well
All divisions of one of my decorative class dahlias has reverted to semi-double this year. Will this condition persist again next year?
It may do Dick. Some types of dahlias, especially if grown from seed, have this tendency.
I have been growing dahlias for many years and started out with several different colors but every year I seem to get more and more maroon with white tips and this year that is all I have except for my small yellows ones that stay the same. What could be making these change colors?
Hi Ed, That’s a mystery. Sometimes perennial plants just degenerate over time, even though they are supposedly ‘perennial’. A bit like us, they’re not always so sparkling looking in their old age as they were when they’re were younger.
If your plants are self-seeding then then they would account for the tendency to homogenise.
Hi Guys i have orange Asiatic Lilies i was wondering is it ok to cut back all foliage as there is new sprouts starting to form on the bottom or do i leave it alone, it had flowered through June and i cut flowers but left all foliage. What should i do now?
Hi Sabrina
Lillies are bulbous plants. The leaves generate energy by photosynthesis that is stored in the bulbs. After flowering, the plant needs to replenish its stores of energy, so it’s best to leave the foliage until it looks really tatty. That way the plant can generate enough energy to store for flowering next year.
I haven’t ever planted a Dahlia, I got one and planted in a plastic pot. The plant itself has grown very large. I haven’t had one flower on it since I bought it a few months ago. There are TONS of buds everywhere. The leaves are dry/hard to the touch and wilty looking. I’ve tried full sun, part sun, everything….what am I doing wrong? ;-( I am thinking about putting it in the ground. But where? in a shady area? sunny?
Hi Emily, it sounds like it’s coming into flower. Dahlias usually flower mid to late summer. Check the roots to see if they’re dry. Wilting can be over-watering or under-watering, so you need to see which might be the problem. It’s good to plant it in the ground if you can. Usually full sun is best, or maybe an area with afternoon shade if the sun can be very hot where you.
When I’ve dead headed my dahlia would the seeds inside grow if I was to plant them?
Probably not Danielle. The process of deadheading stops the seeds forming.
Hi all
I’m a amateur gardener hoping to entry Dahlias in show on Monday, most plants have good blooms on but have not opened yet. Is there any way of speeding up process to get flowers to bloom ?
Denise
I have read through all the questions and do not see an answer to my problem.
I puchased a XXL Durango Dahlia this spring, it was in a pot about a gallon size, had about 6 lovely flowers on it.
I transplanted it in to a pot about 2 gallon size mixed with 2/3 soiless mix and 1/3 rich brown earth.
I fertilized with 10-52-10 @ 1/4 strength for every watering for a couple weeks to get it rooted in. It was in full sun all the time.
It would not do anything in the pot I put it in and all the leaves wilted and then fell off, some new small leaves did grow but then they also turned pale green and fell off.
Finally I tipped the pot over and looked at the tuber and there was not one root in sight, all the soil just fell away and there was a small tuber about 2″ wide and 2″ high. I could not believe the small size of the tuber for such a large plant. I now have it stored in the fridge in a ziploc bag and peat moss so I will try and see if I can keep it over winter.
I have grown dahlias for years and not every had a problem with growing them until now but they were always in the ground and not in pots.
If you have any ideas what could be wrong I sure would appreciate knowing as I would like to try this plant again and have no idea of what I did wrong.
Maybe you gave it a bit too much water and fertiliser. If it had a small tuber a few roots (which you were not to know). then it couldn’t have coped with much food and water. Often retailers force plants on to get them looking good for sale, when they really need to be allowed to develop more slowly so they develop a good root structure.
Hi Martin, I’ve enjoyed reading your great article!
A friend recently gave me 4 massive bunches of Dahlia tubers, not divided. I’m in Los Angeles, zone 10b so not much rain expected and lowest temp will be 41 degrees at end of Dec. Should I store the tubers or plant them in the ground now, or do half and half as a backup plan? Most of tubers look fine but some are looking a bit dried. If I plant them now, can I do it immediately after I divide or should I let the cuts dry for a day? Thank you in advance!
Planting them should be fine if there’s no likelihood of frost, Lucy. Leaving them a day or so after diving is a good idea.
Sorry for the delay in replying
Thanks! I have been looking for this information. I am new to Dahlias and could not figure out if my plant had buds or spent flowers. Your pictures and descriptions are GREAT!
Hi Martin
We live in Southern Ontario and lift our dahlias in the fall.
We started them in pots indoors about mid February.
Now they’re over 3 feet tall and we can’t set them out for another month!
Can we pinch them back or is it too late now that they’re so big?
Thank you
Hi Maureen. You can pinch them back now. They should be fine.
Hi I’ve just bought my first Dahlia xxl Aztec and have found a snail on it, which I removed. Is this bed and how do I stop more coming? As you can probably tell I’m no gardener and am only starting out with flowering plants in pots.
Hi Allison
Yes, snail are not great, but they’re part of a gardener’s life. You can get snail pellets that you place around the plants to deter them. An organic option that many favour is to sprinkle eggshells around the plant. The idea is that snail can’t slide over these barriers.
Otherwise, just keep inspecting and pick them off yourself when you find them. This may be the easiest option given that you’re growing in pots.
Hi there. I am new to gardening. Its winter time here in NZ and mine look like dead brown stalks. Any suggestions?
Hi Chris-Anne – that’s normal. Cut back the stalks and, assuming you don’t get very hard frosts, they should start to regrow in late spring.
Do squirrells like dahlia tubers
I don’t know Betty. But I wouldn’t be surprised if they dug them up to see if they fancied them.
How long do blooms last?
Hi Mary Ann, It depends on the variety, but I’d say on average each bloom will last 7 to 10 days from when it first opens. Keep deadheading the plant and you’ll keep getting more blooms.
The color of my dahlias are faded from the color when I purchased the plant. What can I do to get the original color back. I’m not talking about blooms fading, I’m talking about new buds that open up into a much faded color.
Great article! Thank you so much, this was precisely what I needed to know.
Now I can go and remove all the spent flowers that I thought might be fresh buds hehe
Thanks again, this is excellent
From one Dead Head to another, thank you!
having problems with my dahlias, wonderful healthy plants with LOTS of buds. Problem is the buds will not open or if they do open, the flowers are turning yellowish or the petals are already starting to dry up. I’ve read abouth thrips but I don’t see any signs of them on the plant or the bud or inside the bud. Can anyone help?
Hi Armand. I wish I had a simple answer. It could be a pest like thrips. It may also be related to climatic conditions. If you have had lots of cool wet wether that could affect flowering, as can extreme heat. High potash feed promotes flowering. Perhaps that might help.
I was never a Deadhead but I respect anyone who plays and writes music, they have more talent than I will ever have! Thanks for the info on deadheading my Bishop of Llandaff, I love the dark foilage.
To be honest Jim, I was never massively into the Grateful Dead. But they’re the kind of band that I’m glad existed.
Wow, awesome reading. Would the Dallas grow OK in NZ.
When you pinch them back, there is ofter a hole left in the stem. Is there anything I should do about that, or just leave it alone?
Thank you.
Hi Kimberley. I’ve seen this but never known it to be a problem. Ideally you probably want to pinch out the growing points before the plants is too big and the stems hollow out too much. This will get you a bushier plant. If you are deadheading, then the flower stems are normally relatively thin and not hollow. There is more on this in Dahlias Step by Step
Can someone please help? My deliha is all leaves not sure how to fix it so many leaves can’t see the flowers can I cut the leaves?
Hi Lisa, it sounds like the plant may have been given too much nitrogen rich fertiliser – nitrogen promotes leafy growth. Normally the flower stems rise up above the leaves, but it won’t do any real harm if you have to cut a few leaves off to allow the flowers to be seen. A feed higher in potassium may help the flowers become more prominent since potassium promotes flowers.
For the second year in a row my dahlias are not blooming. (2 different plants) The plant is loaded with buds but they do not open. I have done everything recommended I think. I live in Canada in an area with consistent mid 30s heat. They get lots of water and are fertilized as needed.
Hi. Last year I planted Cafe au Lait tubers in my flower bed, and the flowers were spectacular. They didn’t come up this year, any reasons why?
My mum had the same tubers in a pot, and hers did flower this year.
I’m in the UK
Hi Michele – if you left tubers in the ground overwinter they may have been killed by frost or, more likely, they rotted because they got too wet. There is more on how to overwinter your dahlia tubers here